My house was build in 1890... so yes I have a bunch of issues right off the start but i was thinking of insulating my attic and figured this would be the best place to ask some questions for it has been a long time since I have learned insulation...
Ok first off I would like to insulate the roof rafters not the ceiling/floor...and make a semi livable no heated space... the house has no ridge vent and no soffet vents so I figured it would be allot easier to do the roof rafters... now I know about ice damming and lack of air flow to keep the roof from leaking or crushing some poor person or car with ice! I guess what I’m asking is if I staple all new insulation in the roof rafters and put Gable End vents in will that help my needs at all? Or will I be forced to cut soffet's and a bunch of ridge vents ...which I was trying to avoid... or insulate the floor and the roof rafters and add gable vents??
As it is now there is hardly any insulation in the attic space so anything will be better then what I have now...
You want to keep the underside of the roof sheathing COLD, and to do that, you'll need a vented air space above the insulation, usually 2" is provided. What would be the point of insulating the roof and then cutting a vent into the gable? In an old house, the rafters are most likely nowhere near deep enough to get sufficient insulation plus an air space.
Insulation only delays the passage of heat and/or cold. If there is no heat source, then the attic will sooner or later become about as cold as the outdoors. Or as warm. If your heat source is leakage from the house below, I don't think that's what we are aiming for.
There is a reason that attic FLOORS (not roofs) have been the location of the insulation for hundreds of years. There is no point inventing a square wheel; the world already has round ones.
Architect (NY) and Home Designer (PA)
Posts: 2483 | Location: Tobyhanna, PA | Registered: 24 October 2005
Alternatively you could insulate the gable end walls & underside of the roof with one of those insulations that can be used to eliminate the need for ventilation. There's a code package in the 2004 IRC that has details.
That way it doesn't matter if you have zero insulation on the floor of the attic.
