raft-slab / Green Building & Sustainable Home Renovation Information & Advice

Slab-On-Grade Construction - Technical Guide   Deciding to build your home with a slab-on-grade foundation instead of a conventional basement or raised crawlspace foundation can greatly reduce your environmental impact during construction, and has the potential to offer significant financial savings as well. By replaci...

Slab on Grade foundation, detail design; the basics There are many different soil conditions and corresponding slab designs. This page is about how to build a thickened edge concrete slab on grade FPSF footing on soil with a high water table to prevent frost heave, by first installing drainage below the slab.  Related ...

Materials in a home that act as thermal mass are things like concrete, masonry, ceramic tiles, even a large volume of wood like timber frames. All materials inside the insulated building envelope will store and release heat, the more dense they are the more pronounced the effects are.  Intentionally adding greater amou...

Radiant heating systems are very common in concrete floors now because they provide a very balanced and comfortable distribution of heat. Those systems are most commonly hydronic, meaning heated liquid is pumped through tubing in the concrete which then radiates that heat into the house. View the slab on grade foam for...

The guiding principles during the design of Ecohome’s Edelweiss House demonstration home - passive heating and cooling, healthy living space, affordable to build and operate, resilient and flexible design.  The underlying goal of the Edelweiss House was to design and build a modestly-sized but functional home that wou...

A frost protected shallow foundation (FPSF) is an interesting and well-proven alternative to deeper, more-costly foundations in cold regions with seasonal ground freezing and the potential for frost heave - and the simplest way to build a solid and dependable foundation is to use frost protected shallow foundation (FPS...

Here is our DIY video of  how to lay down tubing for our radiant floor in the Edelweiss House. We have a 10 zone system, allowing floor temperatures in each room to be controlled independently. HePex tubing was provided by Uponor, who also use building plans to give customers a zone plan to follow making the install q...

What is the difference between a slab on grade & a crawl space? A slab on grade, or ‘frost protected shallow foundation’ is exactly that, a slab of concrete on the ground. There’s more to it of course, but let’s start with a ‘win’ in the comprehension department shall we?  A slab on grade rests directly on the gro...

Why build a frost protected shallow foundation using prefabricated foam forms ? Building a frost protected shallow foundation (FPSF) is a well-proven alternative to building deeper, more-costly foundations in cold regions with seasonal ground freezing and the potential for frost heave. Traditional foundations for cold ...

First, the background to this Passivhaus My partner and I are geeks. Our idea of a romantic dream was to build a house so well insulated you could heat it with a hairdryer. For added fun, we wanted to do this on a tight budget while raising a young child. The hairdryer part wasn’t a pipe dream – it’s a common way of de...

WATCH MORE sustainable building VIDEOS Once a decision has been made to choose between a crawlspace or a slab foundation , you need to know how to finish the edge off durably. Typically the exterior edge of a slab on grade is made of EPS foam and can be parged. Having used rigid Rockwool panels meant we needed an addi...