How to build a paved patio with yard that slopes into house?

[ashleyj]

Hi! I am wanting to do a paved patio of about 5x3m. It will be against the back wall of the home which on the other side is a crawl space. The backyard slopes into the house and I want to make sure I'm doing this right and not going to cause damage/water problems to the foundation of the house or the crawl space. Do I need to put a waterproof barrier between the pavers and the brickwork? Or anything else between the pavers and brick work or can I lay them right up against the brick? On the other side of the pavers I will have a small retaining wall because of the backyard slope. If I slope the patio slightly towards the retaining wall to make sure water from the patio surface isn't running into the foundation, should I add a drain along inbetween the patios and retaining wall? Any other advice much appreciated! Thanks

[MitchellMc]

Welcome to the Bunnings Workshop community @ashleyj. It's fantastic to have you join us, and many thanks for your question about leaving pavers.

If you're able to establish a good slope away from the house, then you're already on the right track. In that case, applying a waterproofing membrane to the lower part of the brick wall—just a little higher than where the pavers will sit—can help prevent water from seeping into the brickwork or under the wall. It's a relatively easy extra step that gives some peace of mind.

Since you'll be finishing at the retaining wall on the other side of the patio, it's definitely a good idea to add drainage there. A surface channel drain along the base of the retaining wall will be most effective in capturing runoff from the patio and preventing it from pooling at the base. If you're unable to get enough slope away from the house, then it’s worth adding a second, slimline channel drain between the patio paving and the brick wall to catch any water that may run back toward the home.

One thing to keep in mind when paving against a brick wall is to make sure you're not coming up within 75mm of any weep holes, as you don’t want to block them or allow water to build up near those points.

With good fall and proper drainage, you can absolutely pave right up to the wall without any major concerns.

Please let me know if you have any questions.

Mitchell