Patio and air bricks

[jambojambo]

On one side of our house there is a patio which is: 1) above the level of the air bricks on the house wall, and 2) sloping towards the wall.
Both of these things could lead to damp problems as far as I know.
The long term solution is obviously to replace the patio but what about the short term? I've dug out a trench between the slabs and the wall as a barrier. Trench is about 50mm wide. Will this do until next year? What else could be done?

Any help appreciated, Jambo

 

[noseall]

I would say for every 1.5m of patio you would need 50mm gravel trap. The gravel needs to be free draining and will require maintenance. A better solution would be some Aco drainage.
The air bricks need to be ducted so that they freely vent above the patio.

 

[jambojambo]

Thanks noseall, I'll start investigating that.
Jambo

 

[ree]

Whether you use gravel or as suggested, Arco drainage, you should aim to have your finished level about one brick course below the air brick.

 

[ey143]

I would say for every 1.5m of patio you would need 50mm gravel trap. The gravel needs to be free draining and will require maintenance. A better solution would be some Aco drainage.
The air bricks need to be ducted so that they freely vent above the patio.

Sorry to gate crash, but if we're planning to have a flush threshold patio area (approx 8m deep from the sliding doors), what sort of surface drop will I need to have and is a single drain channel a few inches away from the sliding door the best approach to this?

 

[noseall]

what sort of surface drop will I need to have and is a single drain channel a few inches away from the sliding door the best approach to this?

Aboot 12-15mm every metre.

We try and fall the surfaces away from the building.

Larger areas sometimes need more than one water collecting point, i.e. it is a lot to ask water to travel long distances over big areas.
We did a biggie recently (410 x 600mm x 600mm slabs) and the image below shows a large area. we fitted a pair of gullies centrally to help deal with large storms. The rest of the water runs off to the perimeters and away from the building.

Slabs

• noseall
• 15 Oct 2015

 

[ey143]

what sort of surface drop will I need to have and is a single drain channel a few inches away from the sliding door the best approach to this?

Aboot 12-15mm every metre.

We try and fall the surfaces away from the building.

Larger areas sometimes need more than one water collecting point, i.e. it is a lot to ask water to travel long distances over big areas.
We did a biggie recently (410 x 600mm x 600mm slabs) and the image below shows a large area. we fitted a pair of gullies centrally to help deal with large storms. The rest of the water runs off to the perimeters and away from the building.

Slabs

• noseall
• 15 Oct 2015

Do you have finished picture, I'm curious to see the final finish. Wouldn't having a drain channel in the middle have ruined the effect of the patio? What was the overall patio size approx?

 

[noseall]

The slabs finish level with the blue brick header wall. In other words the wall acts as a frame to the patio and the rain water spills down the blue bricks.
I set the wall 3660 from the house. This equated six slabs plus mortar joints.
The large bit visible is about 8m x 9m square.
I laid the slabs in a half bonded pattern.

Porchpatio2

• noseall
• 15 Sep 2015

I don't have any finished pictures yet, but I may take a few at the weekend when (if) I pop up.

 

[noseall]

I opted for two rain water gullies instead of the channel. Yes, the Aco drains would have spoiled the effect. You can just see the black tops of the gullies either side of the stack of slabs in the first image.

Slabs2

• noseall
• 15 Oct 2015

 

[ey143]

I opted for two rain water gullies instead of the channel. Yes, the Aco drains would have spoiled the effect. You can just see the black tops of the gullies either side of the stack of slabs in the first image.

Slabs2

• noseall
• 15 Oct 2015

Looking good, did you also build the extension? Wouldn't mine seeing the final pic if you remember to post it. not sure if I have come across gullies before. Are they slight raised square drains that the water simply flows into, bit like a plug hole?

 

[noseall]

Looking good, did you also build the extension?

Yes. Completed a couple of years back. there are a few photos in my gallery.

not sure if I have come across gullies before. Are they slight raised square drains that the water simply flows into, bit like a plug hole?

Yes. The whole patio, complete with retaining wall, slabs, gullies etc was set out to the nearest mm. I admit to being a wee bit OCD, but the finished product is quite pleasing.
There are steps outside the bi-fold and tri-fold doors and the patio swings around the side of the building finishing at an oak pillar, hip roof porch.
I will get some piccies on Sat.

Porchpatio

• noseall
• 15 Sep 2015

 

[ey143]

For the patio area, if you were to price a job like that again, what would it typically cost?

Below are some pics of my current extension build and if you can see past the mess, we are thinking of having a 12-15m wide by approx 6m deep patio (4th or 5th fence post).

 

[theprinceofdarkness]

A couple of years ago, I laid a 4m X 8m patio, I just had a 2" fall from front to back, so the water runs away from the house with a 4" side to side slope. So I reckon that the water should end up in one corner. Except for the house wall its basically surrounded with dry stone walls. It has not flooded during Wensleydale winters.
Frank

 

[noseall]

Did you have a look......here

 

[ey143]

I just saw them now, thanks, looks really good. Agree with one of the comments, I perhaps as a home owner would have added a few more things, a bit plane, but looks good.

Could you pls give me an idea of cost of the patio for something of the size you did?
Also how deep was your sub base, hard core etc?