Insulating a Roundhouse Floor

Tony Wrench
Thursday, 1st May 2014

Tony Wrench explains how a new product made from recycled glass is now insulating the floor in his low impact roundhouse.

For several years we have been thinking about doing something about the earth floor of our roundhouse.

We had wood rounds on the bare earth on the outer circle, but bracken still came up in the kitchen each year and we probably lost quite a bit of heat to the floor. That is OK in the middle, since the clay underneath acts as a heat store, but it needed insulating nearer the walls to prevent heat loss all the way round. It was damp too.

This year I came across a fairly new product called Foamglas that is made by forcing air through molten recycled glass to form a very light, pumice-like material that does not wick water and is very good insulation. It looks to me as if it will bear weight well too, so as an experiment we have put down a layer of 20cm (8in) of the stuff around our outer circle, without a membrane, and floated wooden joists onto it, then screwed planks specially cut to a taper by Adrian and his mill up the track.


Four hard working friends helped us for a week and we now have a new, warm, dry floor.

Tony Wrench is the author of Building a Low Impact Roundhouse. The third edition of the book is due in May 2014. Pre-order now from our Green Shopping site. Or download the 2013 updated version available as an eBook.

Further resources

Watch: Building a simple wood and cobwood roundhouse

Building a roundhouse den

Survivng the wettest winter - reflection of a low impact roundhouse dweller

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stuartdelaney |
Wed, 14/12/2016 - 12:50

Flooring is the best part of every house therefore, we choose the best one for our house, which fulfills all the requirements and expectations such as; quality, cost effective, easy to install and requires less maintenance and repair. Here in this article also, we can get an overview of roundhouse floor, really a nice concept.