Attic ventilation / Discussions

How do I prevent attic moisture build up in winter?

I have noticed  heavy frost build up in my attic space the last 2 years in my home. It is 5 years old and had R50 of cellulose fibre blown in when built. The moisture barrier is properly installed and not modified. I got a bit of leakage in the spring through my master bathroom ceiling.  I have a 6/12 pitch roof with g...

Posted by Steve Jensen July 9, 2025 Walls and Roofs

How do you ventilate a roof in a hot, humid coastal climate?

...attic space as it can be. Be sure inputs are not blocked with insulation. There are many designs of roof peak exhaust vents, the ones with the best repuation we have seen are Maximum roof vents as they not only allow air and moisture to escape, the design is such that the wind pulls air from the attic space. They look ...

Posted by Ashok Abhyankar Nov. 29, 2021 Roof assemblies - renovation 1 response

Why do I have condensation on my ceiling and how do I fix it?

...ventilation in your attic to remove moisture or frost will form in winter, which will cause moisture damage when it melts in the spring. And to prevent condensation from forming you need to prevent thermal bridging at the top of your wall, which means adequate insulation. We realize it’s a fine balance and there might ...

Posted by bruce chambers Nov. 5, 2021 Walls and Roofs 5 responses

Why do I see conflicting information on vapour barriers?

...attic voids above closets to seal, and baffles/insulation stops to install for ventilation. All that I can handle. I had another contractor come out to take a look for quoting me on doing the loose fill once all my prep is done. He said to do all the prep I was planning, but not to worry about a vapour barrier; just lo...

Posted by Trevor Karbashewski April 25, 2023 Air and vapour barriers 1 response

Can you use blown cellulose overtop of fiberglass insulation?

...ventilation openings through the soffits. Check this page first about roof ventilation – Why roofs need to be ventilated and how to ventilate a roof properly So that would cover the blown-in aspect of your insulation, but your design in general has me a little baffled so I’ve got no answers but a bunch of questions of ...

Posted by E McKinney Feb. 3, 2021 Architecture and plan design 2 responses