Replace tub surround

[stillworking]

I am replacing the tub surround and faucets and have a question about what to put between the surround and the wall studs. When I took out the old surround, immediately behind it (on the long side of the tub) was what appeared to be 1/2" sheetrock (cracked and crumbly) and behind that a thinner sheet of a wallboard type material, then a very thin layer of paneling, then insulation and a foil material next to the exterior. I know to replace the insulation, but should I use some kind of vapor barrier also? Is greenboard still sold? I read on the internet that it is no longer approved for surrounds. On the two short ends of the tub, there was only the thinner wallboard type material behind the surround. If I do use a sheet of greenboard (or DenShield, which I have only read about) it still isn't going to fill all the space between the tub and studs on the long side. Hoping this makes sense and thanking you for any suggestions.

[Greg]

To do the job "by the book" the tub should come out and the damaged sheetrock and insulation removed & replaced. Green board is still around but quickly taking a back seat to newer products like Denshield. I am told they install just like sheetrock, but I have not worked with any of them yet so I cannot say first hand. Greg

[troyster]

Cement backer board is the way to go for tub surround installations.

[stillworking]

I've read that the cement backer board is a bear to work with - hard to cut and throws off tons of dust. If you have used it - could I ask if that was your experience and what did you use to cut it?

[JD]

While HardiBacker and the like do throw a lot of dust, it is not difficult to work with. It cuts well with a jig saw and carbide blade. I have used a circular saw and 28T carbide blade with success and best part is when you need a straight cut through the piece, you can score it with a carbide scribe and snapping it. Be sure to have the piece supported at the cut. Score and snap creates almost no dust.

The important thing is to do your cutting outside, hopefully with the wind at your back. Wear a mask and those dorky goggles that totally enclose your eyes.

JD

[troyster]

Yes it does throw off tons of dust ,thats why I cut it outdoors. And it is hard on cheap saw blades. I threw my saw blade away after cutting the material but in my opinion its the best stuff in a high moisture water damaging environment. plus its hard to burn. bonus if you need to solder around it.

[stillworking]

Thanks for all the input. I'll be deciding soon how to proceed and will let you know how it works out.

[mobtek]

Handy tip - cut Hardibacker (cement board) with a straight edge and a SCORING KNIFE. Score it - 1 or both sides and gently bend it back and forth and snap it - works like a charm.

If it has to be perfect cut it about 1/4" long and a quick sanding with a block will square it up nicely. Cutting that stuff with a jigsaw or any other saw is a NIGHTMARE of dust and a waste of blades.