If you want to insulate a floor assembly by leaving the joist bays empty and installing rigid foam on the underside of the joists here are a few things to keep in mind.
Insulated timber floor construction.
Unless you are thinking about solid wall construction the fundamental distinction between masonry and timber frame is the non negotiable need to preserve a cavity between the inner timber structural panel and outer.
The effect is a greater sense of comfort and that in turn allows the homeowner to turn the thermostat down.
It acts as a thermal barrier to the heat that escapes from the wooden floor.
Polyester and fiberglass are the cheapest.
Installing any amount of insulation will warm the floorboards and go a long way towards eliminating draughts.
A suspended timber floor tends to be cold and draughty because of the air circulating beneath it.
According to the 2012 irc the minimum r value for floor assemblies is r 13 in zones 1 and 2 r 19 in zones 3 and 4 r 30 in zones 5 and 6 and r 38 in zones 7 and 9.
When it comes to the energy performance of timber frame and masonry building systems there are some key design differences between the two.
Since 1990 when a modern timber floor is constructed insulation is required by the building regulations.
Explore our designs for a look at how we integrate hand crafted timbers with structural insulated panels sips to air seal and insulate your walls and roof.
This insulation is placed between the floor joists.
If the insulation is soft insulation it can be suspended on netting fixed between the joists whereas rigid insulation can be sat on battens nailed to the side of the joists.