Waterproofing and tiling decks

[Rizowz]

Hello all,

Just wondering if anybody has any experience or recommendations for a person/company who specialises in waterproofing decks that are over bedrooms etc?

A bit about my situation which might clarify:

I own a house with two large decks, one extends over and forms the ceiling of a bedroom, the other ajoings the kitchen, which together form the ceiling of the double garage. They leak. The house is a monolithic insulclad house, built in the mid-80's on treated timber. To the best of my knowledge, the leaks only started when the last owners decided to add heavy slate? tiles to both decks within the last few years. It appears they might have disturbed what ever waterpoofing was there.
I intend to pull up the tiles in the next few weeks to assess any damage done. The worst leak through the garage ceiling is pretty bad (e.g. you'd want a bucket when it rains), it's as if the rain is just running through the joins in the ply over the joists. It has done considerable damage to the GIB lining the ceilings, but all joists etc seem to be okay. Once any damage is attended to, I plan to re-install the existing or perhaps new plywood to form the base of the decks. I would like to retain the tiles that are there now, they look really good but are not a must have.
I have seen plenty of companies around the auckland region (house is located on north shore) who seem to offer this sort of service, but I am really looking for somebody who knows what they are doing; I've seen the horror stories of amateurs on the likes of Fair Go doing really poor butynol waterproofing jobs .
Does anybody have a recommendation for a company, installer or product in particular that they have used with good success in a situation like this? There seem to be plenty of products around, Rhino linings, Equus, etc and no shortage of companies applying them, but I am looking for somebody who can provide some good honest advice as to the best cause of action in my situation. Particularly if I'm going to tile over the new membrane, what are the do's and don'ts, whether I should improve the deck base to something better than standard construction ply etc.
I'd imagine somebody who does waterproofing/tiling in bathrooms would be useful, as they probably have to make sure any bathrooms are water tight, especially above ground floor etc.
Likewise if there are any tradies on here who do that sort of thing, or landlors/home owners who have been down a similar path?

Any help would be greatly appreciated, I am new to this property rennovation game and don't want to throw away good money by doing it wrong.

Cheers,
Rizowz

[Vai-man]

There are new rules regarding butynol substrates. But 21mm treated ply is a good start with thicker decking butynol would be the go imo. im not yet sold on the paint on waterproofing.

I dont know anyone in auckland though sorry, if you dont get any recommendations try asking at the ardex store and for previous references.

[Rizowz]

Thanks for your assistance. Can you expand further on the 'new rules' for butynol?

As an update, we have pulled down ceiling gib below both decks that are tiled, and thankfully all joists and other beams etc are in fantastic order. The plywood that forms the deck is pretty damp (soaked through from the top to the joists supporting it. There are pink batts in the ceiling below one deck, interestingly they are covered in damp sawdust (definately not rotten/mouldy wood) so it appears when my decks have been tiled that they have actually removed the existing floor and waterproofing and then just put down ply and tiled straight over the top of it! The tiles I have seen removed support that, who on earth would fit tiles straight over ply with just grouting to keep it watertight?!?!
I think I will rip up and replace the ply unless it is mint (which by all accounts it appears to be waterlogged and probably swollen in places, hence i have water pooling in areas rather than heading to the drains, deck is angled).

The ardex website has some good info on its range of products, as well as registered installers. I'm sure one of those people will be able to give some helpful advice on the best product for my needs.

Does anybody have any experience in this area, maybe you have had a deck or roof waterproofed and could offer some helpful tips or pitfalls to avoid etc, this would be greatly appreciated.

Regards,
Rizowz

[Davco Rep]

Hi Rizowz
Plywood is not a good substrate for decks to be tiled. The preferred choice is Compressed Sheet or Eterpan.
When either of these products have been installed then a Tile Installation SYSTEM which includes a waterproof membrane, should be installed as per specification. (Such as the Davco K10 Water-based Polyurethane Class 111, BRANZ appraised, council approved, UV stable water proof membrane) When cured a comaptible Davco adhesive is used to install the tile or stone.
Problems occur when trying to tile over a membrane that is not part of a Tile Installation System.
For further assistance to find an accredited applicator of these systems you may email me.
Davco Rep

[jimO]

your deck needs to be waterproof before any tiles go on same as tiled showers, there are several roll or trowel on type membranes, this would be my pick...http://www.mapei.it/referenze/Multim...mart_TD_EA.pdf the problem i see with doing a existing deck is your membrane should go up the walls under the cladding and up under the door frames. I also would not use ply if you are going to do a exterior tile deck i would lean more towards 20mm compressed hardies. As you already have a butynol deck i would be more inclined to remove the tiles, cut out the butynol leaving a bit around the edges to join on to, replace the ply, have the butynol replaced, leave it for a while to see if the leaking problem is solved, clean down the butynol with sugar soap, have a proper tiler relay the tiles (doubt you will get the old ones up without breaking them) using...... http://www.ardexaustralia.com/pdf_prd/01230001.pdf thats the only adhesive that will successfully stick tiles to butynol.....also when picking tiles make sure they are suitable to go on a butunol substrate

[Maccachic]

From our website:

By Greg O'Sullivan MNZIBS, FAMINZ Dip. Bus. Stud (Dispute Resolution), LEADR Panel (med) Arbitrator, Mediator, Registered Building Surveyor, Branz Accredited Adviser

At times when I talk about remedial work I feel like I am shouting into the wind. However, if shouting sometimes reaches the ear, then shout I will. It never ceases to amaze me when I come across people who are prepared or willing to undertake remedial or improvement work using what they call a new "super product" and forgetting about simple basic facts of construction. There is no better part of a property to examine this than closed in decks. Whether the deck is 12 floors up in a commercial building or hanging on to the architecturally designed sides of an eastern suburbs seaside property, the same problems arise. What am I talking about? It"s simple. Often I have seen decks built and satisfactorily waterproofed with a butyl rubber. They had the edges of the butyl rubber flashing under doors, windows or balustrade surrounds. Later, a repair occurs and someone chops off the butyl edges with a knife and leaves the bottom edge to flap free. Add to this the latest miracle waterproofing compound, which is laid across the original substrate and has absolutely no connection to butyl rubber. The result is simple – water that comes in through doors, balustrades and other points and used to be directed out by the butyl rubber, is now left free to drip and run inside, causing extensive damage. The "Seekers" song "When Will They Ever Learn" comes to mind frequently when I see these sort of remedial muck-ups. This primitive aspect of construction behaviour is nothing short of amazing. Before employing anyone to do waterproofing, ask questions about flashings to the surrounds. Ask about underflashing the ranchsliders or french doors. Ask if they are going to take your membrane behind the wall cladding, and how. Tradespeople may be competent at laying ceramic tiles and various types of membrane, however, unless they understand the basic design principles of correct side and bottom drainage flashing details, they are unlikely to get it right. It always pays to ask about the effect on other elements in the building. And before you listen to anyone who tells you to replace butyl rubber because it fails, be careful. Though failure has occurred to some joint adhesives, that type of material has given good service to the industry over many years. My call is, "let"s get it right". I constantly say to people, I don"t mind a free five minute call if I can help you get it right. Unfortunately, my experience is that minor defects can lead to major repair costs. To contact Greg, email [email protected]

[jimO]

love it when someone asks a question then never comes back

[Rizowz]

yeah, the question was asked in July 11 and didnt really need dragging up by some salesman but yeah........ kinda sorted now but thanks all for your valued input.