GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Adding new siding in wet or damp conditions

DANIEL LAJOIE | Posted in Green Building Techniques on

From a best practices standpoint along with manufacturer’s recommendations, when installing over the plywood sheathing; building paper (15# tar paper), 1/2″ rain screen and ‘Hardiplank” horizontal siding, should all of the surfaces be dry before installation?

Our rainy season in Portland is almost upon us and I want to know if it’s ok to install these materials when any of these surfaces are wet or will this end up creating a situation where I’ll regret it later. Seems like I see this all of the time. Please advise.

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. GBA Editor
    Martin Holladay | | #1

    Don't worry -- put up your siding, rain or shine.

    All of the materials you mention will dry to the exterior. Once the sun hits the wall -- something that happens in Portland every three or four months -- drying will be very rapid, even through the #15 asphalt felt. The rainscreen will help speed drying.

  2. Troy Farwell | | #2

    I live in Portland and put up siding on a new shop building last fall. I did exactly what you described here - #15 felt, rain screen, then siding. Everything dried out fine with no issues. I did wait until I was sure it was dry until I painted it.

    Good luck.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |