DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Insulation (http://www.diychatroom.com/f103/)
-   -   Cape Cod and 2x4 rafters (http://www.diychatroom.com/f103/cape-cod-2x4-rafters-147489/)

upnorthrunner 06-18-2012 07:13 PM

Cape Cod and 2x4 rafters
 
Hi all!

New here-trying to learn. My 1950 Cape Cod house needs some better insulation. It has 3' knee walls, a sloped ceiling, and a mini attic. I put as much as I could in the mini attic a few years ago and it helped. But the ceiling walls on the slope are 2x4 walls with R11 (far less in some area!) Major heat loss up here on the canadian border...

I have to yank drywall anyway. Here's what I am thinking: R13 in the bays between the rafters..1 inch foil board over the rafters on the inside, seal seams in the foil board, then sheetrock.

Would this work? Be helpful? Am I wasting my time??

Thanks for your feedback.

sixeightten 06-18-2012 07:43 PM

If you are pulling the sheetrock anyway, why not add framing to furr down the 2x4's farther?

joecaption 06-18-2012 08:08 PM

By adding 2 X 2's you could use R19.
You will need foam baffles from the top of the knee walls to where your "mini attic" starts for air flow.

upnorthrunner 06-18-2012 08:54 PM

Thanks, good ideas! Am I on the right track?
The biggest reason I had considered not furring 2x2s was losing the space. It's a VERY low ceiling to start...losing two inches means a lot. This place was built when fuel oil was cheap as dirt and it shows. I guess it's only another inch though.

Yes I was going to install the baffles too.

Code for my area for a cathedral/sloped ceiling is R30 which I can't get to. But i could get to about R19 with this plan. Which is a huge improvement over the current state of R 5 or so....No wonder I get ice dams! It's literally less than an inch in areas...

Windows on Wash 06-19-2012 08:47 AM

Blocker the joists, rigid foam and seal the knee walls, install baffles if you have soffits and intake air. If not, dense pack the slopes and over insulate the flats and the flat attic above.

AGWhitehouse 06-25-2012 02:10 PM

Noone seems to like this response, but it's the best option if insulation efficiency is the goal:

Put the insulation on the exterior side of the roof with "Vented Nailbase Panels". You will need to replace the roof, but you'll save all the interior space and all the crawl space funky stuff will be null & void. It solves the air sealing, thermal bridging, and roof surface venting problems in one application. Just google the name in "" and you'll find a whole slew of manufacturers.

Windows on Wash 06-26-2012 06:42 AM

Quote:

Originally Posted by AGWhitehouse (Post 951352)
Noone seems to like this response, but it's the best option if insulation efficiency is the goal:

Put the insulation on the exterior side of the roof with "Vented Nailbase Panels". You will need to replace the roof, but you'll save all the interior space and all the crawl space funky stuff will be null & void. It solves the air sealing, thermal bridging, and roof surface venting problems in one application. Just google the name in "" and you'll find a whole slew of manufacturers.

I totally prefer that option, however, getting the customer to incur that expense in another question altogether. :eek:

AGWhitehouse 06-26-2012 07:04 PM

Quote:

Originally Posted by Windows on Wash (Post 951826)
I totally prefer that option, however, getting the customer to incur that expense in another question altogether. :eek:

You speak the truth!


All times are GMT -5. The time now is 01:24 AM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved