The Yank's House - Basement Floors

the basement kitchen

The basement floors in the Yank’s house were concrete over rubble. These had been very damp when we first got the house but had dried out well, so we hoped we might not have to dig them out completely. However when Pat’s nephew came to do the plumbing for us he needed a trench dug across the kitchen floor. Ever the romantic, I hoped we would find lovely stone flags but this only reviled the full extent of the dampness — these floors would have to come up.

Pat hates using any kind of heavy equipment or machinery on the house, so using jack hammers was out of the question. I joke with him that he is worried he might hurt the house. I had seen a TV program once where builders had moved a small digger into a house to dig out basement floors. This would never happen in the Yank’s house. Pat approaches every job with care and respect for the building. So digging out the floors was a hard slog.

First the concrete had to be broken with sledge hammers, then the floors were dug out manually with shovels and lastly the rubble barrowed out of the house a wheel barrow at a time. All the while, Pat took care not to damage the structure of the house. For the first time I felt useless. This work was much too heavy for me. Pat’s brother Brendan helped. It took them a week to dig all the floors out. This was the most unrewarding job we had tackled to date. Once the floors were out the basement was covered in muck and looked much worse than it had looked when the concrete floors were there. It felt like one step forward was two steps backwards. Pat said he now knew what it must feel like to work on a chain gang. 

muck floors

I had never imagined such muck and water could be trapped under the concrete. It made me even more determined never to use concrete on the Yank’s House.

Once the floors were out we were faced with the dilemma of how best to tackle the damp. We wanted to put in floors that could breath — in keeping with the approach we had taken with the walls. Putting down plastic and modern insulation was not an option. We had read that this only caused the damp moisture to travel under the plastic towards the walls where it would rise and cause further problems.

I looked into the possibility of using hemp in a limecrete mix but was worried that it would take too long to dry and mould might develop. I sent Edward Byrne (The Traditional Lime Company) a text asking for advice and he suggested I look up LECA, an expanded clay pellet aggregate. I was able to find information about this on the Internet and decided this was the way to go. The LECA comes in two types, coated and uncoated. The coated LECA is used as loose fill insulating aggregate. The uncoated is used with lime and water for a limecrete mix.

Once the decision was made The Traditional Lime Company were able to source the LECA for us.

The floor area was first covered in breathable mesh membrane. This is like the membrane we use in our gardens to keep down weeds. We then spread four to five inches of dry coated LECA 10-20mm over the whole area. These look like chocolate Maltesers.

First layer - Dry LECA

black mesh - timbers for walking on over first layer

Pat builds up layers - wet layer

This was levelled out and another layer of breathable mesh membrane placed on top. For our sub-floors we prepared a mix of three different sizes of uncoated LECA, 1-4mm, 4-10mm and 10-20mm with lime.  This was mixed in the cement mixer at a ratio of 3 LECA to 1 lime with water and applied as one would a concrete sub-floor. This sub-floor was laid to a depth of four inches. Once the new floors were in the basement dried out very well. It was a great success. 

mix for sub-floors

Finished floor

Sub floors down our next dilemma was how to finish them off. Our budget wouldn’t extend to a stone floor and even clay tiles were working out at thousands of euros. Ceramic tiles would create a seal on the floor trapping in dampness so that wasn’t an option for us.I am going to keep you all in suspense for a little while longer ... next posting will reveal all.