Attic Insulation And Ventilation - Building & Construction - DIY Chatroom Home Improvement Forum

Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Building & Construction


Thread Tools Display Modes
Old 10-22-2011, 11:29 PM   #1
Join Date: Oct 2011
Posts: 1
Rewards Points: 10

Attic insulation and ventilation

I'm fixing up an old garage to make it into a building for all of my aquariums. It will be very warm and humid in the building. I live in eastern Washington state. Not seattle (think Idaho or Montana climate). My question is what should I do to the attic? Im assuming I need a vapor barrier on the ceiling. What kind of insulation is best? How much and what kind of attic ventilation will I need. I plan to run a dehumidifier in the building but this space will be kept constantly at 72-75 degrees. Right now there is no ceiling, no insulation, no soffets or vents of any kind so I am starting from scratch and want to do it right. Thanks


Killa is offline   Reply With Quote
Old 10-23-2011, 01:18 AM   #2
Join Date: Dec 2008
Location: Fairbanks, AK
Posts: 1,852
Rewards Points: 1,010

Attic insulation and ventilation

First off, air seal like a madman; every conceivable crack or opening needs to be caulked, foamed, taped, whatever. Google the airtight drywall approach, too (ADA). Blow cellulose into the attic, as deep as you can afford or the sheet rock can support (depends on your spans). As for the vapor barrier, my gut says to avoid it, but that may be one for people who deal w/ high humidity inside, like pools, etc. Ventilation will surely help. I believe the rule for ventilation is 1 sf for every 100 to 150 sf of attic. Have plenty of ventilation, and keep the soffit vents close to the walls to minimize wind washing. Make sure you have at least 2" of air over the insulation near the eaves. If you pack the insulation in tight to the ceiling, you will be inviting icing, etc. If you just can not afford all the cellulose, use fiberglass batts (yuk!) and cover them w/ 3 or 4" of cellulose to prevent them from "leaking".


jklingel is offline   Reply With Quote
Old 10-23-2011, 12:03 PM   #3
Residential Designer
AndyGump's Avatar
Join Date: Sep 2010
Location: Orange County CA.
Posts: 1,350
Rewards Points: 616
Send a message via Skype™ to AndyGump

Attic insulation and ventilation

I think you need to be more concerned with venting the room itself.
You are going to need a constant source of fresh air entering and taking out the humid air, venting this into the attic would not be a good idea either.

AndyGump is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Air sealing, ventilation, and attic insulation project-need advice Badfish740 General DIY Discussions 4 06-01-2011 06:48 AM
Recently Topped Up Attic with Blown Insulation...Now I have Frost/Condensation earthad1 Building & Construction 81 02-18-2011 12:42 PM
Insulation, Ventilation in Cape Cod Side Attic Get'n er done Building & Construction 10 12-02-2010 11:38 PM
Adding insulation and storage to Cape Cod Side Attic turin39789 General DIY Discussions 5 11-08-2010 10:50 AM
Finished attic insulation and ventilation issues diyfreak Roofing/Siding 1 10-07-2008 11:01 PM

Top of Page | View New Posts