Interior timber & flooring

The gap problem

Q: Tried to gap fill then varnish my 50 year-old ash floor, but timber movement resulted in the gap fill cracking out, and varnish not lasting two years. Is there an alternative, with a lasting gloss finish? Read Answer

Timber on a heated floor

Q: I want to put timber flooring on top of a hydronically-heated slab in South Australia. What timbers will be applicable for this application and which installation method is best. (Bamboo has been recommended on a 3 mm underlay)? Read Answer

A question of acoustics

Q: For a live theatre, the acoustic consultant has specified 50 mm insulation with a combination of perforated and non-perforated plywood panels. My main concern is the minimum thickness of plywood lining required from a durability perspective. Floor to ceiling height is 4600 mm? Read Answer

‘Float’ to reduce floor noise

Q: I am renovating a 1970's double brick & tile, concrete slab construction second-storey unit in metropolitan Melbourne. The existing floor covering is carpet and there is a 20 mm set-down at the door threshold (to concrete). I am considering solid spotted gum or blackbutt stuck direct to concrete. How do we reduce noise and would a waterproof membrane be required on the concrete slab? Read Answer

The condensation hazard

Q: I'm installing some exposed slash pine glulam beams in a hydrotherapy pool. The engineer has requested that they be finished with two coats of polyurethane. Our subcontractor has suggested Cetol TSI Satin plus, which was rejected. Can you recommend anything? Read Answer

Karri or stringybark floor?

Q: We're considering karri or stringybark for a living room, kitchen and laundry floor. Is the karri environmentally sound, and are there any other practical issues we should be aware of with either of these. Would a satin polyurethane finish be suitable? Read Answer

Using blue gum outside

Q: We have selected 85mm-wide blue gum for an internal sunroom with polyurethane finish. This floor is to adjoin an external timber deck that is very well ventilated but also quite exposed. Is blue gum OK used externally with an oil finish? Read Answer

Applying adhesive

Q. I’m preparing to lay 80 mm brushbox flooring on a particleboard platform floor, secret nailed with adhesive. I have Bostik ultra set in sausage form and 15 gauge x 38 mm staples. How is the adhesive best applied and what c/c should I be stapling? Read Answer

Floor expansion gaps

Q: I want a European oak floor stuck directly to the concrete slab floor in my family room. The room is about 5 m wide. Please advise how much space needs to be left each side of the floor to allow for expansion - I assume this would be corked? Read Answer