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A subscriber/reader asks “The fiberglass strips of insulation that you suggest be placed between the logs… I assume those are about 5″ wide (cut from 15″ rolls) is it only one strip between the logs that we would need to use or two (i.e., back to back with the paper sides glued together)?

Thanks for the question….. In a couple of earlier posts we discussed insulating between the logs using rolled insulation that I had cut. You want to make sure that you do not compress the insulation it should remain fluffy.

I simply cut the insulation with scissors (mind you I wear one of those paper masks when working with insulation and gloves when handling) into strips — the strips I cut are about 2 inches wide usually. But it depends on the size of your logs.

If your logs are 10″ to 12″ then most likely you will be cutting strips of insulation about 2″ wide — the larger the log the slightly larger the strip - slightly. I’m simply filling the space/gap between the exterior and interior chinking.

I am not creating a blanket to cover the top of the log — only a strip that sets on the very top of the log - chinking will be on either side of the insulation.

This is a single strip - I myself tend to separate the paper from the insulation and just use the raw fluffy insulation. I don’t have much need for the paper.

You asked if I “dust the insulation with boric acid once the strip is laid down on top of a log that is about to be topped with another log”…..

First off — the log wall should already be erected — Don’t insulate until you are ready to chink and that isn’t done until after you have built your structure. In a Butt and Pass log home as you are building (the strongest and best method of construction) you will naturally have space between the logs bottom and top log that will vary.

After I have cut the strip to be placed (loosely stuffed between the bottom and top log so that it remains fluffy) I simply toss the strip of insulation into my bucket of boric acid powder and dredge. Think of it like dredging a breast of chicken in flour.

This will give a light dust of boric acid and thats all you need. The boric acid dredged insulating strip will be encapsulated between the logs (top and bottom) and the chinking (interior and exterior).