Good Day:

I plan on converting mt attic into useable space, actually I have done on the floor, wall, part of teh electrical, heating, etc..now I am tackling the insulation and there are TWO schools of thought out there.

First some background on my humble abode..

Semi detached, raised bungalow, central heating and air.I laso live in a cold climate, we get some snow up here :-)

The first school of thought is to pack the roof joists full of insulation, vapour barrier, then dry wall on top from that point.

The second school of thought is that you must allow the roof to breathe, so you must allow space between each joist for air to flow and circulate. I've seen inserts you can burchase that fit between the roof joists and ensure you have the proper spacing.

So, which is correct? This space will not be a storage area and I plan on finishing it off properly, so a lot of time and some money will be put into it and I'm not interested in having my roof ice up and my shingles peel up and leaks start because I've insulated incorrectly.

Any suggestions or advice would be super appreciated.

Hi consolinc,

Your project will require a LOT more planning if you're asking questions like this. I'm not trying to say you aren't doing the right thing by asking questions, because you ARE doing the right thing. Since you're doing this work yourself, consider spending some of the $$$ you save on Professional costs by spending it on a GOOD book, or 2.

Regarding your ?, yes, you need to allow the roof-line to breath. You'll need soffit vents and a ridge vent. You'll also need soffit chutes which run on the underside of the roof's sheathing. You shouldn't need a vapor barrier because you have one on the roof already (called tar paper.) If you add one now, you'll only create a 'pocket' for moisture to get trapped in between the 2 layers, and start rotting. Yes, add insulation AFTER you add the soffit chutes.

Have you considered if your HVAC system can handle the additional demands for that space? Have you 'evaluated' your floor joists, especially if they're not at least 2 x 10's? (You'll be putting furniture and flooring and the weight of people up there so it has to be 'sound'.) How 'bout electrical demands??? Will you be running new lines to 'service' that space? The same for phone and CATV and who-knows-what-else. (You can NOT run both types of lines w/each other.)

I guess I could go on and on but a good renovation book that talks about 'converting' an attic into living space already does that for me. My best to ya and hope this helps.

Jay J -Moderator

PS: God Bless America!

Jay:

Thanks for the insight.

I will certainly invest in a quality book on attic renovations.

My ace in the hole is my father, a civil engineer and a commercial building (retired) contractor, so all of the drywall, electrical, etc is covered off well. The only outstanding issue was that no one has ever done an attic renovation.

Take care, I appreciate your help.

Regards,

Peter