The climate the type of foundation whether the slab includes hydronic tubing for radiant heat and the severity of the local termite problem.
Insulating concrete slab on grade.
From a radiant heating perspective it doesn t matter if the slab is actually at grade or is poured several feet below grade as part of a full foundation.
It seems like it should not be so complicated.
By replacing concrete with lower impact and better performing building materials like.
Insulating a slab on grade depends on at least four factors.
Slab is one foot or less below grade r 10 insulation required extending 2 feet below grade for climate zones 4 and 5 4 feet below grade for climate zone 6 insulation should extend downward from the top of the slab with two options to reduce slab edge insulation r value.
Martin holladay explains insulating a slab on grade in the energy smart details department.
One arrangement may be more conducive to maintaining a continuous thermal barrier from a wall down through its foundation but it allows unsightly exposure along the.