About 6 7 inches between the slab subfloor with always.
Insulating a floor from above.
Is it okay to place fiberglass insulation between joists that are on a concrete slab with osb subfloor above.
From above or below.
4b slab floors built directly on the ground.
The goal however is the same.
It s easier to insulate if there s access to the floor from below and you won t have to disrupt the floorboards here left quilt insulation is pushed between the joists.
Also insulate 4a any portion of the floor in a room that is cantilevered beyond the exterior wall below.
There are two ways to handle insulating concrete floors.
When insulating from above right a loose fill insulation such as cellulose is breathable and will fit into every nook and cranny.
If you have 2 inches of insulation your floor has an r value of 6 4.
Gaps negate the r value of the insulation.
To prevent air leaks it s important to install caulk at all of the indicated locations.
There are two types of crawl spaces ventilated and unventilated and each requires its own form of insulation.
Without insulation heat and cool air are easily lost through the floor.
Floors above cold spaces such as vented crawl spaces and unheated garages.
This will be heated living space.
Thanks for your help.
Clayton ebsch march 26 2018 at 4 35 pm.
Insulation also helps to preserve the air quality and reduce energy costs.
Floor above a garage this detail shows a garage bonus room floor framed with open web floor trusses.
In those days common building practice was to insulate the floor above the crawl space and to leave the crawl space s wall vents open so any moisture buildup would vent to the outside a.
To insulate the floor of the room above the garage seal the space between the floor of the room and the ceiling of the garage and the top plate and the header joist with insulation.
An insulated floor can make a garage much more comfortable to work in during cold weather.
This can be done through blown in insulation and unfaced or faced batt insulation.
Another significant detail is to make sure the insulation is held tight to the bottom of the subfloor.
4c as an alternative to floor insulation foundation walls of unvented crawl spaces.
You can attach wood sleepers to the floor fill the gaps with rigid foam insulation and then apply your finish flooring.