We have recently laid solid wood flooring in an open plan kitchen, dining room and snug. Before the job commenced we aclimatised the wood in the room for a few days. It covers a large area and has been nailed to certain areas of the floor where possible and floated on concrete (new extension area). Glue has been used all planks. We are now experiencing rafting (gaps in wood), particularly near the radiators. Can anyone offer any advice on how we resolve this problem. We have avoided putting beading on the edge and keep hammering the wood to reduce the gaps which works for a few days. Would anyone even suggest not leaving an expansion gap on certain small areas to keep the wood from looking like "lightening has struck"?
When you say "new extension" and "floated on concrete" how old is the concrete. Concrete takes many months to dry thoroughly so this may be one problem.
Aclimatising the wood takes a few weeks in opened packs not a few days. This could be another cause for concern.
You say you have nailed some boards and floated others, where did you use the glue? was this used on the joints of the boards to seal the surface?
Rafting (Cummulative shrinkage) is caused by the individualy planks of wood shrinking but unable to do so evenly. This tends to happen when the boards have been bonded together, the strain builds up and suddenly gives only along the weakest joints. Thus your lightning strike effect.
Fillers are about the only solution but you should wait to see how far the shrinkage goes. It may reverse when everything settles down.
Many thanks for your reply. We used glue to bond each plank together at the joints. The concrete was new but had been put down in June 07 and the wooden floor was completed in November 07.
If we hadn't bonded (glued the wood together) would the wood have been saved from causing the lightening effect? I ask this because we could relay some of the wood in some of the worst areas and omit the gluing part.
The wood is drying out at the moment, (Central heating = lower humidity) this causes it to shrink and the gaps appear. If you can re-seat the wood to remove the gaps I don't see a problem. If you install new wood that was spare and has been in the garage or shed you will find that will shrink as well, although more evenly between boards without the glue.
It probably will not look worse if that is a consolation.