I am building a house and have a 4 foot catilevered deck. The roofers applied a rubber membrane over the plywood and water is now collecting and leaking back into our master bedroom on the plywood. I checked it with a level and it sloped ever so slightly towards the house. Should I install a drain or take off the rubber membrane and shim to create a slope away from the house. Don't know how to solve this.. . HELP!! I will provide pictures later today.

Take off the membrane.

If this is a balcony that is constructed using floor joists from the second floor, you'll never be able to change the slope now.

Deck should pitch 1/4 inch per foot or 1 inch away from house.

Do u have enough room to raise the deck floor 1'' plus at house wall.

If u are getting water in, my guess is that u have a problem with the flashing at the wall. Was there flashing installed at house wall?

How is membrane finished at house?

There are 2 ways it could/should be finished.

1. Membrane run up under siding with a canfer strip under membrane at wall.

2. Membrane run up to wall. Flashing set in roofing cement on top of membrane and run up under siding.

In both 1 & 2 membrane/flashing should be under house wrap as well as siding.

If unable to raise deck at wall, get back to us and we will attack that problem with u.

Good luck

Chuck

If u have room to raise deck at house, u will have to remove membrane and plywood.

Install wedges on top of beams to give right pitch. Make wedges out of ripped 2 bys. Install plywood and new membrane.Be sure to flash deck to wall as I stated above.

Chuck

If you are going to remove the membrane and ply,I would cut the joists to the taper 1/4" per foot,this would make it a permanent fix.

Hi KBC

It would be easier to add the wedge then to cut the existing beams in place. U would also have to cut the box beam which might be double.

U would also be reducing the size of beams and may cause the deck to structural soundness.

If deck is pitching 1/4 per foot toward house, u would have to cut from 2'' to nothing or 1'' to nothing and reverse the piece u cut off and nail it back on to get the 2'' u need.

Easier to nail 2'' wedge and not have to worry about structural.

Chuck

Hi Chuck,

I guess I was thinking of mine(I have both front and back cantilevered decks),on a 2X8 joist,the necessary strength would need to be at the pivot points, namely at the house, if the outer edge is trimmed towards the inner(pivot),and then reversed, making the outside cut 1/2 the depth needed for the reverse slope... yes,then it would be 1" to nothing on the 4'.

I guess I would have to be there to see the extent of the backwards sloping and decide from there.

and,, this is(us)presupposing that they have space for the rise.

The wedge system is what we used on extensions when doing flat roofs when bottom of rafters was the ceiling.

U are correct that we are guessing that there is enough room to add wedge. But it gives PO the option

Chuck

Hi. . Thanks for the responses.. . I am going to have the roofers remove the membrane and try wedging like you guys explained. I may consider doing a Duradeck type material so that it now becomes a non issue once it is sloped properly. I will let you know how it goes. Thanks.