MatthewC
Member
- Messages
- 1,733
- Location
- Central/South England
Due to dampness and rot of the wooden floor, not to mention poor drainage and high ground outside, we're laying a limecrete floor in part of the church (and raising the floor level by 150mm). This is also addressing other issues like the mud under a solid floor (caused by the ingress of water through an airbrick as the drain outside has been blocked), and the steep slope of the wheelchair ramp will be reduced.
Three years ago I did a limecrete floor in this house (see my blog at http://houseintheenchantedforest.blogspot.co.uk/2011/04/fitting-limecrete-floor-part-1.html and subsequent) and I've been surprised at how things seem to have changed since then. On my floor for the hardcore, I spurned the little lumps of Recycled Foamed Glass (RFG) and used Light Expanded Clay Aggregate (LECA), which was difficult to tamp enough but not too much (as it can crumble). LECA was also used in the slab with NHL5, and the screed was just NHL5 and sand.
The materials are all from Ty Mawr and they have a new (to me) type of hardcore. They now have "RFG Gravel" (see http://www.lime.org.uk/products/limecrete-and-sublime/components/recycled-foamed-glass-gravel-rfg-glapor/) which is a very different product to RFG. It is VERY lightweight - a one tonne size dumpy bag weighs about 60kg I'm told. This is very strong and does not crush, and can be tamped very hard without suffering.
The church floor is basically this design: http://www.lime.org.uk/products//limecrete-and-sublime/labc-registered-sublime-limecrete-floor/ but has a 100mm slab on top of the hardcore, and then the heating pipes are in a 50mm screed which is what they are laying now. For both slab and screed a dry mix sold by Ty Mawr is being used, which is mixed on site with NHL5 and water to produce the right consistency - the screed is a lovely dry-ish mix which tamps very well.
I think there's probably a cost issue (which I think is why I used LECA) but apart from that I'd certainly recommend this design for anyone doing a limecrete floor in the future (that is, until they come up with another improvement!).
Matthew
Three years ago I did a limecrete floor in this house (see my blog at http://houseintheenchantedforest.blogspot.co.uk/2011/04/fitting-limecrete-floor-part-1.html and subsequent) and I've been surprised at how things seem to have changed since then. On my floor for the hardcore, I spurned the little lumps of Recycled Foamed Glass (RFG) and used Light Expanded Clay Aggregate (LECA), which was difficult to tamp enough but not too much (as it can crumble). LECA was also used in the slab with NHL5, and the screed was just NHL5 and sand.
The materials are all from Ty Mawr and they have a new (to me) type of hardcore. They now have "RFG Gravel" (see http://www.lime.org.uk/products/limecrete-and-sublime/components/recycled-foamed-glass-gravel-rfg-glapor/) which is a very different product to RFG. It is VERY lightweight - a one tonne size dumpy bag weighs about 60kg I'm told. This is very strong and does not crush, and can be tamped very hard without suffering.
The church floor is basically this design: http://www.lime.org.uk/products//limecrete-and-sublime/labc-registered-sublime-limecrete-floor/ but has a 100mm slab on top of the hardcore, and then the heating pipes are in a 50mm screed which is what they are laying now. For both slab and screed a dry mix sold by Ty Mawr is being used, which is mixed on site with NHL5 and water to produce the right consistency - the screed is a lovely dry-ish mix which tamps very well.
I think there's probably a cost issue (which I think is why I used LECA) but apart from that I'd certainly recommend this design for anyone doing a limecrete floor in the future (that is, until they come up with another improvement!).
Matthew
