No Sheathing Under Siding

We are installing hardie colorplus lap siding over e t1 11.

No sheathing under siding.

I m do a re clad of a wood framed building. Tri level home built in mid 70 s with 4 stud walls with bat insulation without any sheathing under masonite sheet siding with battens on 16 centers with no vapor barrier of any kind 3 8 or 7 16 siding then 3 1 2 insulation 3 8 drywall between me and the outdoors where siding joined between upper lower sheets no z bar installed only lapped over approx. If i add 3 8 ply then siding will be proud of corners and casings. There is no sheathing.

The wood that goes under residential siding exterior sheathing performs several functions. 1 no flashing windows or z. Call it what it is an idiotic installation. Trim is elaborate and ornate so not replacing.

It also provides a. In theory the sheathing on your home should never get wet as long as the proper preparations are made when siding the home flashing house wrap j channel caulk etc. We are also re building these 10x10 decks with a 2x4 framed guardrail. I have seen houses with no sheathing old or non structural sheathing new and the foam could absolutely be structural enough to support the siding as long as adequate bracing is done it really doesn t matter.

Tonight i was replacing some outdoor lighting only to find to me surprise this house has no ouside sheathing. My main concern was a wrb covered drainage plane which i was misled into thinking wasn t there. Vinyl siding is a rain screen only and is not waterproof. It adds insulation waterproofing and structural support for the framing.

The construction from outside in is. Using 1 2 x 6 clear cedar bevel siding and since no sheathing insulation can be fiberglass any recommendations. While the installation of the vinyl siding without sheathing or housewrap behind it may be technically legal it is not good building practice and quite frankly is stupid. Or do you always need sheathing when doing hardie lap siding regardless.

Where you ll often see plywood used instead of osb is in roof sheathing where the risks of moisture and leaks are greater.