BASC Search | Building America Solution Center

Rigid Insulation Over Aggregate

CAD File

High-Performance Slab-on-Grade Foundation Insulation Retrofits

Reference

Report assessing slab-on-grade foundation insulation energy savings.

Right - This rigid insulation is correctly installed in a level layer over aggregate; the seams will be taped

Image

Capillary Break Beneath Slab - Polyethylene Sheeting or Rigid Insulation over Aggregate or Sand and Geotextile Mat

Guide

Guide describing how to install a capillary break under a slab foundation using either polyethylene sheeting or rigid insulation installed over aggregate or over sand and geotextile matting.

The builder’s crews spray foam directly onto the ground to provide a vapor barrier and insulation layer under the slab.

Image

Right – Workers lay radiant floor loops over the concrete reinforcement which is laid over a heavy vapor barrier installed over the sub-slab insulation before the slab is poured.

Image

This Texas homes uses a slab foundation including a 4-in.-thick post-tensioned monolithic slab with turned-down edges poured over a 6-mil polyethylene vapor barrier and capillary break; slab edge insulation is not used due to termite risk.

Image

Passive House Underslab Foam & Vapor Barrier: Karuna Video #6

Video

Video describing the under slab and vapor barrier used on a passive house.

Wrong - Polyethylene sheeting should be lapped up sides of walls and pillars and taped

Image

Right-Polyethylene sheeting is correctly installed over aggregate and taped to pillars and foundation wall

Image

Right – Workers pour the concrete for the basement floor slab over a vapor barrier installed over rigid foam.

Image

Polyethylene Over Aggregate

CAD File

Radon Fan

Guide

Guide describing how to install a radon mitigation fan to actively remove radon from the home.