I make my own wood preservative. I could run out and purchase a similar preservative for about $95 a gallon or I can spend about $10 and make my own. I make a simple mixture that I can use in a garden sprayer on my logs.
My ingredients for a home-brew exterior wood preservative include are simply two things: a borate-based product such as Timbor or Penetreat and Propylene Glycol (environmentally friendlier, marine and RV anti-freeze).
People have asked “Why Penetreat or Timbor when for just a couple of bucks they could use 20 Mule Team Borax (Thats right, the laundry and general cleaner). After all it has borates in it and isnt that the same stuff?” No.
There is no doubt that 20 Mule Team Borax is a wonderful cleaner and I use it here at the lodge for many things however it is not the same stuff. Borax is sodium tetraborate decahydrate, a natrually occuring mineral, an inorganic salt. Boric acid is the result of borax reacting with a mineral acid such as hydrochloric acid. The resulting boric acid, trihydroxidoboron, is a great antiseptic, insecticide and flame retardant.
Boric acid kills wood destroying insects and also prevents and destroys existing wet and dry rot in timbers but is the more refined crystalline material used as an antiseptic and is not readily available in useful quantities for wood preservation however, borate-based products are.
Borate-based products such as Timbor or Penetreat both containing the borate Disodium Octaborate Tetrahydrate are excellent and easily obtained.
Both products can be applied dry or dissolved in water in order to make a paintable or sprayable solution of a desired concentration. The solution is best used on bare wood. For interior surfaces I make a 10% solution by mixing one (1) pound of the borate for each gallon of water. For exterior surfaces I will use the same mixture but for certain exterior areas I take an extra step.
On the exterior when I need to treat log ends or wood is subjected to more extreme conditions I make the solution above but instead of using water I use propylene glycol.
Why propylene glycol?
Propylene glycol although does kill existing mold and mildew as well as many wood boring insects, whats more significant is that it is hygroscopic. this means that when sprayed on a log end or exposed grain it follows and attracts the water or moisture from deep in the wood. The water is somewhat ‘replaced’ by the propylene glycol. When mixed with the borate to a 10% solution this becomes a very effective heavy duty preservative.
When the two are used together the borate dissolved in the propylene glycol is pulled deeper into the wood especially when applied to the log ends. As the propylene glycol dries the borate powder crystals will reform.
Propylene glycol is also easy to get. Propylene glycol is the base for earth-friendly antifreeze. I go to the local auto parts store and get a gallon of environmentally friendly antifreeze. If you are planning on making your own then CAUTION: READ THE LABELS! DO NOT under any circumstances use antifreeze with a base of, or containing any amount of ETHYLENE GLYCOL. This is nasty stuff folks DO NOT use. Ethylene glycol can be fatal and must be avoided for this application.
If you are thinking of making this preservative then take every precaution necessary. This post is not meant as a “go out and do it” only as an explanation of what I do. As in the handling on any type of preservative or insecticide YOU are the one ultimately responsible for your actions.
With that said – Now, how do I find propylene glycol based antifreeze? I read the label. I ask for RV and Marine antifreeze then read the label again to confirm that it is propylene glycol and NOT ethylene glycol. Propylene glycol based antifreeze is generally used as an additive to potable water systems in addition to being an engine coolant.
Making the propylene glycol and borate wood preservative is easy.
Similar to the 10% borate-water solution but this time instead of water I pour one gallon of propylene glycol into a five gallon pail. Next I very carefully and gradually add 1 pound of the borate-based powder. Stir slowly adding a little at a time making sure to dissolve the borate powder. Now the mixture is ready to be used.
To make a 15% mixture add 1.5 pounds of borate to each gallon.
I used this propylene glycol and borate preservative mostly to treat log ends where the natural capillary action of the wood can also wick in water. I will also use the mixture on select out of reach areas where I know environmental exposure is greatest. I liberally paint or spray the log ends with the preservative a little at a time to make sure that it soaks in. I have also treated checks (cracks) that may apprear on the upper part of a log before sealing.
I do not go spraying this on broadly across my logs and on all exterior wood — I only use it sparingly and for very specific and select spots.
I never use the propylene glycol and borate preservative on the interior anywhere nor do I use it in areas in close proximity to or probable contact with anyone.
There is a method to create a concentrate by heating the propylene glycol to reduce the water content and then disolving the borate to make the solution. I have done this – but for very specific and limited projects.
If heating the propylene glycol to reduce it – this should be done outdoors only and with the proper safety gear such as long sleeves, gloves and eye protection.
Before applying the preservative to the wood I take the basic steps to make sure that the wood is clean of dirt and debris.
Feel free to leave a comment or a recipe that you have successfully used.
{ 74 comments… read them below or add one }
I was looking at your home made preservative just making sure you are talking boric acid. I am an exterminator and have ready access to boric acid pouder
Hello Kevin — The ‘boric acid’ referred to is actually a borate based product- rather than straight boric acid. I use both Penetreat and Timbor which are borate based products made specifically for this purpose.
Hello, I have a gallon of Borrada ,an imported Bora-care , which has come out of solution. Is there a way to reconstitute the mixture? I have made the DYI product successfully.. Thanks
Hi…Bearfort…What a GREAT WEBSITE.. I was looking for a homebrew recipe to treat my house underneath on the sill & floor joist ends lying on the sill.What would you recommend as a fungicide & wood preservate.I think i have caught the wet rot before having to do extensive repairs.This will be underneath the living area so i assume it would be safe to use there.I would like to apply it by using a tank sprayer.i would appreciate a comment & the recipe you would recommend for this project. I only need to treat about 35 ft.
Love your site. I have a twenty-year old cabin we built with ashe juniper logs. I just purchsed the Penetreat for the exterior, but the interior has insect damage also. Can I use the water and borate preservative inside or do you have another suggestion for interior logs? Thank you so much for all the help you give those of us who are trying alternative solutions. Anna
Hello Anna – Thank you!
As far as treating the interior – Yes you could use the water borate but remember that when it dries you will have a white film on the logs – this is the recrystalization of the borate when it drie. With that in mind I would not use the borate water mix on the interior. However what you could do and what I do here at the lodge is use the borate in a squeeze bottle to ‘puff’ a little around the interior foundation. I will also use dry borate and puff into out of the way places (places where pets and people cannot access) as well as into any gaps you may have between logs and chinking on the inside. wipe away visible signs of the borate but try to get it into cracks or checks where you know you have insect patterns. I would concentrate efforts on the exterior as well as around the base log on the interior where it meets the foundation – this should be in your basement or crawlspace.
I’m trying your mixture on my pine railings ( 2×5″ round, with 1.5″ spindles). they were installed about 2 years. They were stained, but for some reason, were never sealed. I have friends with a log home built by the same contractor, and their pine railings are completely rotted. The wood in some spots is turning black, and I have fungus growing out some of the tracks. I have build 2 forms that will hold a 5″ round. I plan to soak one of the rounds for 2 hours and then flip it over. I then plan to fill the checks, re-stain and then seal them. Do you have any advice on what I am about to do?
Thanks in advance.
Hello Ernie — sorry it took so long to respond. I believe that this is cause for a conversation – look to your email as I will send you my phone number and we can talk about it.
I have access to a bunch of long, 4-6 inch diameter fir logs that I am planning on using to make the framing for a pole barn style chicken coop. I will use your borate and water preservative solution on these logs. But do you think I need to do even more preservation of the log ends if I set the ends of the logs into the ground about 2 feet deep? What would you recommend for log ends set into the ground about two feet deep? Creosote or roof tar?
Hello Ty — Cool project.
Hmmm. Honestly I would avoid sinking any of the logs into the ground at all opting instead to keep the fir log end up off the ground by at least 6 inches. No matter what you use on the log ends the fact that you are sinking them into the ground and fir is a pretty soft wood — I’d have to give you the heads up that their strength and longevity will be drastically reduced to a blink. Id hate to see you go though such effort to find out in a couple of short years that they are rotted out.
I would suggest instead digging holes where you would have sunk the log ends and use 8″ foundation tubes. You can find them at home depot — sink them to below the frost line mix and fill with the appropriate concrete mix and while the concrete is still wet sink into the top a foundation bolt, tie down or anchor. Once cured your post can set down on top of the cement foundation pylon and be anchored down . Cover the base of the cement pylon with stones if you want so as to make it look like your logs are going into the ground. But if you want your logs to last a long time keep them out of the ground. Even the borate and glycol mixture in a highly concentrated form would not be able to prevent buried logs from succumbing to rot.
for example one of the first rules when building a log home is never ever build a log home where a foundation or base log is indirect contact with the ground. Logs must be off the ground no less than 6 inches at least in order to help prevent rot.
You dont see too many log structures or other wood structures where the logs, timbers or wood and especially the framing is in direct contact sitting on the ground or buried even a few inches below the surface – well you dont see many of them because most of them have rotted away , collapsed and become part of the soil.
I love the concept of the pole barn coop but do yourself a favor and save yourself from certain heartbreak and secure your logs above ground to your foundation pylons. Foundation tubes are inexpensive – you dont really “need” the tube though — dig the hole nice and clean and straight about 2to 3′ deep to get below the frost line and about 8″ diameter. Dig one hole for each log – fill the hole with cement and add the anchoring bolt — probably a 6 inch long 1/2 anchoring bolt with about 3″ of the bolt exposed above the concrete. Drill a hole in the bottom of your log slightly smaller than the bolt to get a tight fit and drive the log down over the top of the bolt – now at least you have the log end off the ground and securely on the top of the pylon where it will last a very long time without rot. Periodically treat the ends of the logs at the foundation with the glycol mixture maybe once or twice a year for good measure.
Good advice. I would add to install rebar in you concrete foundation posts . Also, I have found that putting posts into concrete in the ground causes them to rot out faster because the concrete absorbs water. Best as you suggested to put the wood ontop of the concrete and fasten it to the concrete.
Leonard – You are correct.
is this recipe basically the same thing as bora care? and, is it the same strength? boracare states that it is 40% dot with glycol added. it is then mixed 1:1 with water for active termite infestations. (my house is an old wood florida “cracker style” house built up on bricks with an open crawl space. i can’t tent it right now, and there is nothing to stop a reinfestation afterwards anyway, but i need to try something for at least a temporary fix.
i’ve read tons about both tim-bot and boracare. if i have to buy either, i would need the latter. (the old beams are untreated.)
sure would rather save some money though. boracare is pricy!
thanks for the help
Hello Will — Yes pretty close to Boracare – using Timbor or Penetreat for the borate base
Is it safe to treat wagon wheels, carriages, sleighs, etc. with the boric acid – polypropylene mixture? Do you need to warn visitors not to touch the items once it was applied? We currently just use boric acid solution. Would the mixture discolor the wood in any way?
Hello George – First off – I have never experienced the propylene glycol mixture to cause any discoloring however I think it would be wise to test it on a inconspicuous area first. As far as treating the wagon wheels and other carriage parts – keep in mind that the propylene glycol mixture is most effective when you are applying it to wood that has been subjected to wet conditions on a regular basis and where the moisture has soaked into the wood and conditions are right for rot. — The propylene glycol with follow the moisture into the wood and contaminates the moisture in the wood with enough toxicity to kill off mold, mildew and fungi. So the mix is best used on already damaged wood to stop and prevent rot. Treating something like the items that you mentioned – if they are in solid and without rot damage I believe that it would be in your best interest to take a more preventative approach by treating the items with the methods described by Michael Dutton in the two articles, Traditional Log Cabin and Timber Preservation Practices of Michael Dutton and
Finish Treatment of Timber Using Natural Preservative: Michael Dutton I believe that these are excellent preventive measures.
As for people in close proximity to the propylene glycol – Even though propylene glycol is relatively more environmentally friendly than ethylene glycol I would would be hesitant to use it on items that would be in direct contact with people. Once the glycol is dry there is even less need for concern however I wouldnt use it on those applications.
Take a look at the above reference articles and I believe that you will find that they are much better wood preservation options for you in this instance.
i am wondering if you think this mix would work on our house?
Our home was originally a large (30X60) Amish chicken coop, that was built 40+ years ago. The coop is sided with tongue and groove lumber, and in one corner the rain/storm water runoff -before we added gutters- has done a lot of damage. We are currently replacing the rotten wood, and i would like to put some kind of treatment on the new siding. Also -since it is a very non-traditional house- along with all the other differences, we have a pretty steady stream of bugs (especially carpenter ants) who like to crawl all over the siding and occasionally come thru the walls.
i had heard a mix of borax and linseed oil painted on would take care of bug problems and would also act as a preservative, but i can not find any info on that mix.
Wondering what you think i should try?
—thanks, linda
Hello Linda –
Great project – You may be interested in the articles written by Michael Dutton that address using linseed oils. They can be found both here and here. Using a borate based product is recommended. I would definitely use a borate based product to help ward off insects. Sounds like you are on the right track.
Question: I plan to use this formula to treat my wood fence to extend the life of the fence panels. Do you add any tint to your mixture or would that chemically cause a problem?? Should I “tint” the wood first then apply the preservatives. The cost of store bought preservative has just gotten ridiculous. Thanks!!!
Hey Tyler – I don’t really know if tinting the preservative would cause a problem or not – I’ve never tried to do so. Just to stay safe I would tint or stain the wood as a separate application. Perhaps stain first then when nice and dry use the preservative.
I know that when I have refinished furniture I stain before I put on the wax — I know this is a little different but I would stain first.
I just ran across your web site.I wonder if you have ever tried your preservative on milled lumber?I’m replacing slats in a fence of untreated white pine I built 17 years ago.The slats don’t touch the ground but have suffered from rot at the lower 5 inches.Do you think soaking the lower ends in a bucket of preservative before I apply and paint the slats would work to preserve them?Will the preservative affect paint retention?If you have any thoughts on this please let me know.Thanks,Leo
Hello Leo — thanks for visiting the site. I hope that you found useful information.
I have in fact used the propylene glycol on milled lumber – I have taken both fence boards as well as fenceposts and have let them stand in a bucket of propylene glycol – I have let them soak (I only soak the bottom ends) over night but that is probably not necessary as an hour or two should suffice. The glycol is hygroscopic so the water the carrier and it is this moisture content in your lumber (with a little help from the natural capillary action of the grain) thats going to pull the glycol and dissolved borate into the wood. This process works best in lumber with a high moisture content. If the wood is kiln dried then the glycol will probably not permeate as much of the wood.
I make and use the 10% borate solution as described the article that you read – the Home Brew Preservative.
I see no reason to treat the top of the boards or posts since the problem moisture is that near the ground.
Also- I do not spray down milled lumber since very little of the glycol is absorbed into the wood along the grain – so you’ll just be wasting material and getting that crap all over the place. Using the woods natural wicking action is much more efficient.
The glycol basically replaces the moisture in the wood and also carries the dissolved borate. As the glycol dries the borate crystals reform in the wood.
I have not had any problems priming and painting treated boards however — you do have to make sure that it is thoroughly dry before doing so.
Check out the article “Log Cabin and Timber Preservation Practices of Michael Dutton”
Let me know if this has helped. — If you have any other questions I will do what I can to help — Feel free to call me at that number below if you wish to have a conversation about it.
Thanks!
Where can you purchase these products for the mixture. I can find the marine antifreeze, but not the other product?
This post is very helpfull.Thank you very much.
I would like to know how long keep this mixtur and how long keep after mix water.
another thing is I would like to know the recepe in metric scale
If u dont mind pls send me above for my better knowle.
Thank u very much.
Hello Nishan – Thank you for your interest. I’m not quite sure why you would choose to store the mixture for a period of time. I make enough for the project at hand and have no reason to store it. You should only make as much as you need for your project. I believe that if you store it it will separate in which case you will simply have to redissolve the borate.
Thanks for your reply……….
what temp. is achieved when mixture is adequately boiled?. What dangers are with ethylene glycol?
I have no idea what the temperature becomes when I have heated it for making a concentrate — I simply reduce the propylene glycol by about half. Ethylene glycol is very toxic – that is the bright green antifreeze that is commonly used in automobiles – - what ever you do do not use ethylene glycol
Boric Acid available from Hardware stores and Lowes,
$4-$5 /lb., as:
Zap a Roach
Hot Shot MaxAttrax Roach killer
Propylene Glycol available from NAPA stores and online,
16/gal., as:
SIERRA Antifreeze
Hope this helps. Blue skies.
Good Day,
I’m sorry about the question but being the Propylene Glicol an alcohol will it not evaporate completly as you heat it to reduce the water contents of the mixture?
It’s point of evaporation is not inferior to the one of water?
Thank you
Miguel
Hi Paul
If I’m using the mixture right away you said you don’t have to boil it. Is the recipe the same. 1 gal prop antifreeze,1lbs boric acid. And does it work as well as the concentrate method?
Hello: I would like to do two things for my logs (approx 18 yrs old):
Anti-insect them, and restain them. I plan to power wash first.
The former owner who died, said he used a homemade recipe for stain provided by some Forestry Division. It contained diesel fuel, linseed oil, and something else I believe. I was thinking of adding some oil based stain and experiment with some small mixtures. Do you have a diesel based stain recipe? Thank you
Howdy David –
Dont do the powerwash. Power washing a log home can be one of the most destructive things a person can do to a log home. Don’t let anyone ever tell you otherwise. The goal is to keep water off and out of you logs. Power washing can introduce and force water into areas that cannot dry easily.
If you have to ‘wash’ you logs do it using damp rags and spot clean.
I’m aware of a recipe using a raw linseed oil and a thinner or carrier but I don’t have the recipe. I dont know anything about using diesel based stains.
Sorry about that — Thanks!
I have built a workshop out of landscape timbers, I’m ready to apply a wood preservative. If I have read your recipe correct, I will be mixing;
1 gallon of RV antifreeze
4 pounds of mule team
3.5 pounds of Boric acid
Mix this all togethere and spray it on.
Is this correct? I dont have to cook it down, I can apply after mixing?
I can’tfind boric acid except as an ingredient in roach killer, where can I get this stuff? Please help as I believe my logs are desperatly in need of a preservative before moving on.
Thanks
Lanny
Hey Lenny –
Its 1 gallon of RV antifreeze and 1 pound of borate. You can’t mix in 7.5 pounds of a dry powder and get it to dissolve in 1 gallon of liquid. BOrax found in 20 Mule Team works as a great cleaner but really is not the same thing as the borate.
SO making a 10% solution would be 1 pound of borate and 1 gallon of water. dissolve the borate and you can put it into a sprayer and apply -
You could use the roach killer as it does contain borates – which is its base ingredient – but be tremendously careful as I dont know what else is in roach kill. You only need a pound of borate.
In my locale (Honolulu), industrial quantities/types of chemicals are pricey – even boric acid is now semi-controlled by industrial suppliers, for sale only to licensed pest control people (though still on the shelves at the drug-store’s pest-control section in quart-sized powder…) As I think another commenter mentioned, it would thus be preferable to me to shortcut your three-component process to just two – combining propylene glycol (I think available as antifreeze) and mailordered powder disodium ocataborate (Timbor, etc via ebay). But that’s only if it even /works/ to mix up the stuff that way. To come up with a concentrate with these two components only, would it just be a matter of cold-mixing the two ingredients in proportions derived from what you describe above (say 1 gal glycol to 7.5lbs dry disodium octaborate powder), or is there some need to COOK them to some temperature?
Hello Dave –
Yeah the borate in Penetreat is commonly used in pesticides like roach powder. Propylene glycol is the pink antifreeze found as marine and RV antifreeze.
Timbor or Penetreat are both very good products. Make a 10% solution first you can always increase the concentration. Borate Glycol mix should only be used on the exterior – I only use it for log ends checks, knots and other exposed grain spot applications. The borate water 10% solution can be used for more general applications on exterior. Dry powder application of borate is great in the crawlspace and like areas.
For most application you do not have to cook down. I only cook down or make a concentrate when Im making large quantities of a Boracare like solution. You can make your 10% or stronger solution cold.
How often would logs need to be treated with the borax, boric acid preserver? I did mine when first built and haven’t noticed any problems. But this treatment needs to be done while logs are “thirsty” and it can soak in. I’m needing to re-finish/stain my logs again and wonder if I should also treat them again.
Has anyone ever added this type of preserver to a stain?
the glycol is technically a “surfactant” that causes penetration deep into the wood.
Hey Carl –
Any time that I am going to be restaining I’ll also treat the logs with a 10%solution borate / water. I use the 10% or stronger borate glycol mixture for exterior log ends, knots and checks.
I have a buddy that makes his 10% solution with borate and the stain that he uses and that makes good sense.
You are right the glycol acts as a carrier but also the propylene kills fungi.
Your website is wonderful. Lots of information I need, and easy to understand.
We are refurbishing our 50 year old, vertical log home in NW Washington. There are lots of checks, a few that are deep, but all are vertical. Leaf cutter bees have been drilling into the logs. We are sanding off the old stain, since our chinking does not inspire confidence to use a pressure washer.
Our next step will be to make some of your homemade preservative, and spray it on. We will use it immediately after making it. I’m thinking I don’t need to boil out existing water, and reconstitute with water, but I will heat the antifreeze to help dissolve the borax and boric acid.
Here are my questions. Should I use the antifreeze based preservative on the whole outside surface, not just ends, to maximize protection, or is the water based solution just as effective. I’m thinking that getting in the checks would be good.
You said that you never apply your concentrate to the wood. If I just use the amounts you recommend for making the preservative, and don’t boil off any liquid, should I still dilute 1 to 1 with water before applying?
How long should we wait after application of the preservative before we finish up with some sort of stain and sealent?
I’d sure appreciate any further help you can give me. Chris
Hello Chris – Thank you.
Glad to hear that you are not using a power washer — that is one of the most destructive things one can do on a log home. SOrry to hear about the carpenter bees — They are a problem out this way too.
You are using the mix right away just mix and use. No reducing using heat no just mix and go. Start with a 10% solution of borate such as Penetreat or Timbor and water. For log ends on the exterior only use the 10% borate and glycol mixture.
The water based is very effective for wide areas. Get it into those checks. If you like you can use the 10% borate glycol mix to spot treat checks on exterior logs only.
You can stain over the borate water mix after it has dried without having to brush off the dried borate that may show on the log.
I have a log bud that is making a 10% mix of borate and his stain. Makes sense to me I dont see why you cant.
I like to try 4 lbs borax and 3-1/2 lbs boric acid into 1 gallon propylene glycol but I am not sure that 7-1/2 powder can be dissolved into 1 gallon glycol. I made several tests to dissolve various quantity of borax into boiling water. There was a limit that could be dissolved. One borax supplier made a test, adding borax one by one spoon and stopped when it could not be dissolved. Another supplier said you can not add too much borax. I hope glycol does not like boiling water.
Hey York –
3 1/2 pounds of borate will not dissolve in one gallon of anything. Start with making a 10% solution borate to glycol. You can increase the concentration of borate but only a little at a time. There will be a point at which no more borate can be dissolved and you need to stop adding borate well before that happens.
dear bearfort,
this is the second try to reach you. i will however keep on trying. my challenge is to :
a) waterproof wood slats in a environmentally safe manner;
b) render them termite proof.
i think i can use your boric acid /water mixture alright, but can you suggest a waterproofing agent that will be compatible with the boric acid/water mix?
i think you are rendering a remarkable service!
Hey Wally –
Did you not get my response? I would do just as you suggested with the borate water mixture. That would be the most environmentally friendly. Once dry You could apply a raw linseed oil to your boards. I don’t really have on hand a good raw linseed oil mix recipe for you – I know that there are other elements to it but I have to admit – I don’t have the recipe. I’ll do some research on it though.
Thanks!
Hello,
I am looking for a wood preservative formula that can use Glycol Either. I was given a 55 gal barrel of G.E. and would like to use it to make a wood preservative for new air dried pine 4X4 fence post. I do not have any other use for the G.E. and do not know if it could be used in a preservative. Any suggestions will be most appericated.
William Fox
Hello Wllliam – Glycol ether? Glycol ethylene? I guess you could prepare a 10% solution with the GE and borate. Don’t try cooking it down just mix, dissolve and use. Please what ever you do make sure that you take all precautions.
Hi. I got busy and tried to make your B+prop-glycol preservative. the purpose is to eliminate PPB. I used 1-borax [solubore] agricultural. 2-boric acid.{powder] 3-prop-glycol 95%=additives5% in 20L. pail called Solar2 which is diluted 2-1 for solar panels. I diluted the solar2 1-1[50%] and followed your recipy. Used a lobster cooker for outside use [worked real good] . Poured conc. into washed 1 gal jug. contents has virtually solidifued.what have i done wrong/or is this how it should be. how do i get it out without cutting the bottom of the jug.It seems to be a way to much solids for the amount of liquid. rsvp. yours alan ps .I am from canada and there are no products such as boracare etc. registered or available here. try site bambooman.com. [3kg. borax+2kg Boric acid in 45L. water =10% salution.]
Hey Alan — Thanks for the info I’ll check it out. – The borate should dissolve – is it possible that you added too much? – The purpose of heating the mix to to help dissolve but in the end what I’m making is a Boracare like substance. Sometimes I do get a little bit of slids in the bottom but they when stirred up will again dissolve.
Hey Bearfort, very cool site and I’m glad I found your formula for preserving logs. I’m a log carver (chainsaw and hand tool) and was wondering if you had any great formulas that could be applied to green logs to prevent cracking/splitting. I’m in Texas and carve pecan, which splits aggressively, and cedar, which cracks a lot without splitting. I would like to carve a log and not watch it split down the face of a beautiful Indian, horse, or eagle. Can you help me?
Best, Mike
Hey Mike –
Thank you, I appreciate that. I’m glad that you found some useful info.
Thats a tough one. Cracking and splitting of logs as they dry has a lot of different factors. I think that may have more to do with carefully controlling the environmental conditions during the drying process. If the wood dries to quickly I would think it would be more prone to cracking and splitting.
I understand. It would b heartbreaking to have a log split after you have done such beautiful carving. I have been to your website — Absolutely beautiful.
Attention readers check out Mike’s website Carved Wonders.
sorry, i made a mistake on my email address, I have corrected it now.
Hi There, I am wondering if this solution is safe to use on the inside logs of our home. Also, did I read correctly that I do not have to cook the solution? Can I just mix the ingredients then apply right away? I am thrilled at finding this site, all other preservatives were so expensive.
Thanks for your help, Monique
Hello Monique –
I would not use the borate propylene glycol mix on interior logs as this is meant for exterior only. The borate glycol mixture is primarily used on exterior log ends. That is correct – you do not have to cook it down. Yes – you can mix the ingredients and use right away. Glad that you found the site helpful.
Hi,
I used boric acid in between walls of house I re-did in Louisiana 20- years ago–I never had roaches, termites or other bugs.
We are siding a little 20×20 cabin with 1/3 pine log premanufactured siding.
I have two questions:
One, if we are going to use this mixture right away–could we just make the mix in the dilute form (so we would add one gallon of water to your base recipe) and start brushing it on both sides of the siding as soon as it has cooled. Wouldn’t this keep it in solution easier?
Two, my husband is convinced that we need to use a stain/sealer on the wood–can we do this after “treating” the wood with the borate mixture? And could you make a recommendation on what to use that is reasonably priced?
Thanks,
sherry davis
Hello Sherry –
Yes dry borates used to dust surfaces is long long lasting — a little goes a long ways and it can last for years.
Yes — just start with a 10% borate to water mixture cold — be sure to dissolve the borate – and you can place in a spray bottle i you lke and spray the area. I would use the borate / water mix first – let it dry then aply your stain seal.
As far as a stain seal. I use Weatherall UV Guard. It may not be the least expensive out there but I believe it to be the best.
I made a solution of 1 cup Borax, 2 cups boiling water to dissolve. I added this to 1 qt plumbers antifreeze and approx. 2-3 qts cold water. My cabin is 11/16 tongue and groove boards and required 2 gallons for one “coat.” So far I haven’t noticed the ants “repopulating” but time will tell…
Hey Patrick — Nice job
Hello Greg — Sorry to hear about you situation. NO – you do not have to cook it down – it CAN be used right after mixing. You can pray the material on the affected areas. Apply liberally on the ends of the logs as the capillary action of the wood will help to pull the propylene glycol mixture into the log. You can spray the entire exterior with the mixture – HOWEVER.
I would make a mixture with the propylene glycol and boric acid or Penetreat on the end of the logs. For the rest of the log I would use just a mixture of the Penetreat (boric acid) and water mixture.
The boric acid will dry out and kill off the mold as well as kill off insects.
The only time that I use the propylene glycol mixture is for rotted wood which I apply to the ends and the particular area of rot.
Can the solution of boric acid and water mixture be used to clean chinking and I’m assuming it would also prevent (or/& kill) mold and mildew on the chinking?
I’m new to log cabin restoration/maintence as we’re just getting ready to move into a home that is a partial log cabin.
Love this site! I’ve learned a great deal!! Thanks for the help!
Built our log home in 1979. Have a major insect, mold and fungi problem. Found your recipe for the RV antifreeze, Borax and Boric acid. Do I have to cook it or can it be used right after mixing it? Is it just the ends of the logs you spray or the whole house. Would appreciate your response.
Thanks
Greg
Hello Monica -
Here is the best place to get your boric acid
Give them a shout and speak with Mike. The boric acid comes in a bucket and is very very reasonable.
We have been peeling logs for our home for a week now. We want to put some sort of preservative on them. But we have found that boric acid is really expensive – only place we could find to get it was a drugstore. Is there somewhere else to buy it cheaper? We are also wondering why you can’t put propylene glycol mixture on the inside half of the log?
Hey Randy — Thank you — I appreciate that
The propylene glycol will kill off the mold, mildew and fundus and help to prevent the log from further rot — the bet thing however is to trace back to the root of the problem.
Water can travel in strange ways — and its always best to stop it at the source.
Is there a particular situation?
I loved your site!
I was wondering if you new how to stop aq log from rotting more. If it has started already
I loved your site!
I was wondering if you new how to stop aq log from rotting more. If it has started already
COULD YOU E-MAIL THE MOST SIMPE SOUTION TO PRESERVE MY LOGS….ALSO DO I USE THE PRESERVATIVE ON THE LOGS PRIOR TO THE CHINKING…..WHAT WOULD YOU SUGGEST TO PLACE BETWEEN THE LOGS BEFORE ADDING THE CHINK…..APPROX.3-4 INCHES GAP….THANKS JBR
Jerry –
There is a bunch of information here on the site regarding log preservation. There are also a few recipes. Simplified – A 10% borate (Penetreat) propylene glycol mixture for the ends of your exterior logs. Propylene glycol will follow the moisture and pull in the dissolved borate. When it dries the crystals will remain in the wood and will help to protect against wood boring insects. Along the length of the logs on the exterior you can use a 10% solution of borate and water. Spot treat knots with the borate glycol.
Over the long term keep you rlogs as dry as possible.
Hey Paul it is unfortunate that you had such a tough time with the mixture.
Ive been making it and using it successfully for a long time.
Id be more than happy to talk to you about it — Ive sent you an email with my phone number.
Thanks! — Yes — I have received your email and number and will give you a shout.
How much lime putty do you normally make?
I figured out what was wrong. I misread the weight on the 20 Mule Borax box. I thought it was exactly 4lbs and it was 4lbs, 12 oz., so I added to much borax on the first batch.
Also I found I went through this solution pretty fast, so on the next 7 gallons of glycol I made it just before I was going to use it. I found that if I brought the glycol (in one gal. batches) to a boil, added the borax, brought it back up to a boil and added the boric acid and brought it back up to a boil again, it would thoroughly dissolved everything. I then added water to make two gallons and used it a few hours later. This saved a lot of time and it also applied easier when warm, as a cool glycol solution tended to clog the nozzle on my sprayer (even with the correct mixture). I also found that it was much cheaper to just go ahead and buy 50lbs of boric acid then to buy a little at a time. Overall, I used 35 lbs. to do my cabin and have 25 lbs. left over
.
It applied pretty easy, but in a few spots, I may have sprayed on to wet as I now have to go over with an Osborn brush to take the white crystals off of the logs. The crystals come off easy and I have to do this anyway since I had the logs corn blasted and it leaves the logs kind of roughed up, although it doesn’t look like it. Thanks for the great money saving idea..
P.S. 8/29/07: I’m going to be chinking with a lime mortar of which the limestone is going to the kiln tonight to make my putty.
Hey Paul — Hmmm — Im not sure what may have happened – I have not had that situation. You will find that a great deal of the boric acid does not dissolve completely but I have never had it turn hard on me. I hope that you are doing this on a burin outside — and that if you made it in your kitchen that your kitchen does not have the lingering smell of a garage.
I do believe that if you stir in either glycol or a little water you should end up with a slurry that is more manageable.
This it out with either glycol or a little water. — Glycol has a reaction when on the stove that when heat is applied for a period of time the water will evaporate off – however there will come a point at which the glycol will begin to evaporate as well leaving you with a brick of material. It sound like somehow you passed that point.
The mixture is still usable with a little dilution. The point of the glycol is that it will follow water into the log and with it pull the crystals of boric acid. Both materials will help to kill rot/mold/fungus and bugs.
Hi,
I tried making your borate solution yesterday. I followed your directions almost to a T. I actually stopped before 260 deg. because it was becoming to hard. So I mixed in a bit more of the Propylene glycol and that seemed to have made it a bit more workable. I then poured it back into the gallon jug which with all ingredients did not fill it. Today it is a solid block. I used your recipe of 4lbs borax, 3.5 lbs boric acid per gal. of glycol. Any ideas of what went wrong, of did you use yours right off of the stove? I’m soaking the jug in hot water right now to hopefully turn it back into a liquid that can be mixed with water. Thanks, -Paul
Moving and Restoring a Hand Hewn Log Home
Paul, as addressed in the previous post, is tackling a major rebuilding and restoration of an outstanding hand hewn log home that he disassembled and moved from Pennsylvania to his property in West Virginia. Disassembling a log home is a long laborious…
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