We are preparing a rental kitchen floor for sheet vinyl or VCT tiles. We currently have exposed 3" wide fir strips as the sub-floor. We were told we needed to lay 3/8" plywood over the fir for durability, but the plywood and the thickness of the vinyl raises the floor more than we would like. A second opinion suggested we use 1/4" Lauan, which appeals to us more. Does anyone know if this product is as durable as plywood?
Well technically it is plywood, it's just not very good plywood. Having said that I've seen flooring guys use a product that looked very much like luan that was no more than an 1/8 of an inch thick to get the level they needed. This was in a hospital remodel so it was definitely up to code and it went under a commercial grade thermo-sealed floor so it should be good for just about any application unless your subfloor is really atrocious. Ask around at a dedicated flooring supply store and they should be able to point you in the right direction.
If your sub floor is stiff enough, you can get by with 1/4 plywood. If it bounces, flex's between the joists or creaks when you walk across it you will need a thicker plywood on top to help stiffen the floor.
But in general, vinyl is very forgiving as long as the floor it is going over is smooth.