Water Proofing an Existing Shower - Help

[Tim77]

Hi all,

I have just had a building inspection done on a house I'm looking at purchasing. It's a private sale through the owners that I know.

The building inspector said probably the only moderately concerning issue is that he tested the shower for moisture and the floor showed a reading of 16%. He said that anything over 8% becomes a concern.

Thinking ahead (ie I buy the place) I'm in two minds what to do. The property is 13 years old and I would like to brighten up the bathroom at some stage but waterproofing the shower is the priority.

Options 1) Could I waterproof the shower somehow without lifting up the current tiles? Even if this was possible, would this still not fix the current issue of mositure underneath the current tiles?? OR 2) will it be necessary to lift up some of the tiles, assess the situation, waterproof (using some system) and replace the tiles (assuming there are some originals??). OR 3) could the current surface be treated somehow and new tiles placed over the top? 4) ??

Of course even if option no 3 was possible, this sends me very quickly down the renovation path and this is not something I want to do straight away.

I need to get the problem fixed, properly, shortly after moving in, so I have peace of mind. I just wish I knew more about the anatomy of a shower.

Any advice of any kind, information or resources will be greatly appreciated

Regards

Tim

[Carpenter]

There are no quick fix's for leaky wet area's. You do not state whether the sub floor is a concrete slab, or bearer & joist with either particle board or fibre cement sheeting. If its a bearer & joist construction & there is dampness, you may find the floor framing has developed fungal decay, further compounding the reparation work. The other problem for you is that specialised waterproofers like I use (Wetseal Australia) would typically treat the entire bathroom as the area to be waterproofed, not just the shower area. They provide a warrenty for their work but only if the entire area is waterproofed to their satisfaction. I don't think you would find a professional willing guarentee a portion of the entire area, so you're more than likely looking at a bathroom renovation if there is a failure of the waterproofing membrane. This is a common scenario.

[Tim77]

I'm 99% sure the sub-floor is a concrete slab.

[Carpenter]

Thats better in that you wont have to repair structural flooring, but if the membrane is compromised, there is no quick fix. If the shower has a hob, it may be possible to just remove the tiles in the shower floor area & also the hob, & the new waterproofing could be done in the floor & up & over the hob. This would at least keep the shower sealed, but you still have a less than ideal seal where the new membrane meets the old. Thats why you may find a pro reluctant to do it. Good luck.

[journeyman Mick]

For a temporary fix you could dry the shower out (put a fan heater in there for a few days), rake out any loose grout and replace and then paint a proprietry sealer over the lot. Not sure what it's called but there is one made that supposedly fixes leaky tiles and grout for a while. I think we may have discussed this before here, so use the search function, it may even turn up the product name.

Mick

[Tim77]

To quote the inspectors words "The shower base is leaking and should be caulked and given a clear waterproof sealer"

What's your opinion on this? The inspector said it needed immediate attention but didn't say it was a major emergency that didn't have the potential of being fixed.

I'd like to know what the potential cost of fixing the problem in case I want to change my offer, but without knowing the extent of the problem obviously it's not possible to have an idea as to the cost. I can't get an expert in to look into it because the place has tenants.

From memory, i don't think the shower has a hob. I thought it might be possible to pull up the floor tiles, and wall tiles up about a foot, and then some outside the shower a reasonable distance. Dry the area as required, waterproof, and then re-lay the tiles.

If I then renovate, apply more waterpoofing solution to the surface and tile straight over the orignal tiles.

[journeyman Mick]

What the inspector was saying is basically what I've suggested. I reckon it's on;y a temporary fix though, but should get you out of trouble until you're ready to renovate.

Mick

[Tim77]

In the event of a renovation, would it be possible to Waterproof the surface as discussed and then tile straight over the top? Would this effectively fix the problem, assuming all care and attention was given to the renovation?

Or would the problem cause the renovation to require the removal of the existing tiles and then start again in terms of a water membrane/water proofing?

[journeyman Mick]

Tim,
I wouldn't recommend it, it'll raise your floor level for a start which is only minor but will give you more work when you have to cut your door down and make a threshold. Best bet is to do a temprary fix now, then rip it all out and apply a new waterproof membrane and start anew. Do it right, do it once - which is obviously not how the original builders of your bathroom were thinking :mad:

Mic;

[Tim77]

Thanks Mic. At this stage I don't know whether the moisture is due to cracked grout or what have you. My intention would be to renovate the bathroom anyway (it's not very big either) so a temporary fix might be all that's needed. That said I better not let a temporary fix be temporary for a few years.

I was looking at some products online. Crommelin have a Shower Sealer. Which looks like the type of product I would use.

[gnu52]

Tim & Mick,

It may be the sealer is a product/system called Megaseal.
Operates as a franchise in major cities and has a do it yourself kit for other areas. Hav'nt used it personally but local real estate agents after a quick fix on rental properties tried to talk me into using it. A google search should bring it up.

Spent an hour yesterday looking at a similar problem in a local house, someone has built a shower on a slab by setting bricks in mortar as a hob and then packing mortar under quarry tiles to get a fall to the waste, there being no allowance for a shower tray & water appears to be getting under the tiles and seeping into adjoining wall cavity and bedroom. He has the fall in the bathroom proper falling to the doors, a real tear out job.
Good luck, Bill

[mic-d]

As a short term solution like Mick suggested, you could use a topical system like the Crommelin shower sealer and re-silicone all the corners. But it is only a temp fix, you should never rely on the tiled surface as the waterproofing layer. It really is relatively little expense to gut a shower and resheet, waterproof(use a professional), retile. You can even use the shower screen position as the limit of the demo. and if you can't get the original tiles, then you can make it a feature, for example. You should also check the plumbing. Seal the top side of tap flanges, check the tap stems, shower rose are not leaking into the cavity. Also check that the shower frame is not leaking, some brass ones have a tendency to corrode at the junction between the shower upright and the pipes from the taps. The cheap way to check this is cut a hole in the wall behind the shower if you have ready access and observe when the shower is on. The expensive way is to get a plumber. They will ensure the taps are not leaking (replace jumper valves and reseat if necessary) then fit a pressure gauge where the rose fits and pressure up the system, ie turn on the taps and then turn them of. It is a closed system so a pressure fall would indicate a leak. Clearly it's important to esure the taps are not leaking!
Cheers
Michael

[Carpenter]

Just thought of something else Tim, if there's water geeting where it should not be, you may also run into more damage . Often the wall plates & bottom of studs will be stuffed as well around the shower area. I reckon if your trying to negotiate a price, in all honesty it wouldn't be unreasonable to factor in the cost of a bathroom reno, because its highly likely it will need to be done & at least you wont be out of pocket if you've allowed for it in the purchase price!

[Tim77]

Tim & Mick,

Spent an hour yesterday looking at a similar problem in a local house, someone has built a shower on a slab by setting bricks in mortar as a hob and then packing mortar under quarry tiles to get a fall to the waste, there being no allowance for a shower tray & water appears to be getting under the tiles and seeping into adjoining wall cavity and bedroom. He has the fall in the bathroom proper falling to the doors, a real tear out job.
Good luck, Bill
Bill, my gut tells me this is the same situation with the property I'm looking at buying. How much do you think it would costs to renovate a small bathroom if I discover the place I'm looking at at the same problem?

[Tim77]

Thanks guys. I think I said in an earlier post in many ways it would be so much easier if I already owned the place. That way I could just get in and take a look.

Lets assume that it's not good and the only solution is to get the professionals in, start again...basically talking what would be a full renovation.

By the looks of the floor plan, the bathroom is about 2.6 x 2.6 so it's not very big. Anyone care to suggest what a full renovation would cost? We're talking new bath, vanity, shower screen, tiles, but it's not a family size home so it would be a moderate renovation.

[Carpenter]

Somewhere between $8 - 10,000?