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Insulation help

Beach house on north shore of Lake Erie right on the beach. It's wonderful! 100 yr old wood siding was repaired and replaced as needed last year, professionally primed and painted. It has all blistered and fallen off like dead leaves!

We had installed a vent-free gas stove. Not realizing the impact of the water vapour in a sealed house that on an average day has an ambient humidity of 72% on the INSIDE!!!

Benjamin Moore technician said we should have used linseed primer. Have striped house but can't paint because of constant rain. BM said to not paint until it is insulated.

Here's the problem: nobody can agree on what we should use. John Mansville rep recommended installing solid foam with foil in both sides and to push it right up against the back of the wood siding.

I'm thinking that the wood is wet, even on the interior side and needs to air and dry. I'm thinking we should pull out the foilfoam, turn up the heat, dry it out a bit and then insulate the interior and paint the exterior.

This is a very very humid environment both in and out. Everyone else has vinyl or cement board. We really wanted to stick with the wood.

Would be grateful for any input.

Re: Insulation help

You don't want the insulation up against the siding, you need some air flow behind the siding. The first step is to lower that humidity inside the house and I'd start with finding a way to vent the gas stove or buy a vented gas stove. An unvented gas stove creates a lot of water. You could also buy a dehumidifier but venting the gas stove may be all you need.

When you get the moisture level down to around 30% and the wood dries out, prime (oil based) the inside of the wood first. Then insulate with faced fiberglass batts. Staple the wings of the facing to the inside edge of the studs instead of the inside face as you usually see done. The wings should overlap a little on the ends of the studs. Make sure you have repaired any wiring or plumbing issues in the walls first.

If you have water lines in your exterior walls, all the insulation should go on the outside of the pipes, otherwise you want the insulation right up to the inside sheathing (sheetrock) with no gap. Any gap should be on the outside between the insulation and the siding.

After the rain stops and the wood is dry, prime with an oil based primer, then paint with two coats of a good latex topcoat. Don't make the siding so tight that a little air cannot get in and vent the insulation. A little venting the insulation will keep it dry and make it more efficient.

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