Concrete Patio Clearance to Siding

[carle3]

I have always worked with the notion that a concrete patio should at minimum have a least 2" of clearance from the last row of siding. I have a client that would like me to come over and evaluate his patio. In the phone interview the concern is over the distance to the siding. In preparing for this, I was researching this 2" clearance and I have not found any creditable resource for my position.

Our code is for 8" earth to top of foundation clearance. Any specification on concrete patio is nowhere to be found. We are not an IRC state but even that seems to be lacking. I am not in a termite area so there is no specification for an inspection zone being left. I have found some talk of a 2" splash zone to untreated wood products but I have not found a creditable resource to quote for this.

Anyone have any direction to point me for a standard of practice on a concrete patio?

[Brandon Whitmore]

What kind of siding is it?

[carle3]

Hey Brandon,

Don't know that yet. I will be looking at it tommorow morning.

[Chris Bernhardt]

What's the clients concern? Is his siding deteriorating?

For cases where I don't have a hard code or standard that I can throw against the wall and hope it sticks, I put the recommendation in a form that I learned from Walter Jowers.

"If you don't want your (whatever) to (do whatever you don't want it to do), you'll need to (Write in what ever you think is good advice)."

Chris, Oregon

[hausdok]

Hi,

Don't know about code, but James Hardie prohibits their siding installed any closer than 2 inches to any surface where water will pond and there is a spec in the stucco manual that talks about keeping the bottom of a stucco'd wall not less than two inches above flatwork.

OT - OF!!!

M.

[Brandon Whitmore]

The best code reference I can find if wood siding is R319.1.2, but is siding really embedded in concrete when concrete is just poured against it? Kind of stretching it.

If it is a man made product-- manufacturers installation instructions will rule.

[Mike Lamb]

I don't think the IRC is lacking.

R404.1.6 Height above finished grade.

Concrete and masonry foundation walls shall extend above the finished grade adjacent to the foundation at all points a minimum of 4 inches (102 mm) ...

A concrete patio is a finished grade. This does not answer how close siding should be to the grade but foundation above grade is more important.

[Brandon Whitmore]

A concrete patio is a finished grade. This does not answer how close siding should be to the grade but foundation above grade is more important.

What do you think about the concrete steps poured on the patio and against the house wall/ siding for the step up to the patio door?

[carle3]

Thanks Gentleman for all your good wisdom. It is a help and does allow me to speak with some knowledge going into this. I think all points are valid and is one reason I continue to frequent this place. If I find something of interest I will post it and pictures.

Thank You

[Mike Lamb]

Re: stairs against the house, I don't think about it much, unless it tips towards the house or is causing some sort of problem.

[Brandon Whitmore]

Re: stairs against the house, I don't think about it much, unless it tips towards the house or is causing some sort of problem.

Yeah Mike, your post just made me think of it-- it's a big pet peeve of mine when they pour concrete against perfectly good siding. I'm getting irratated just thinking about it.

[hausdok]

Hi,

I'm guessing that Mike L. is responding to Brandon.

Folks in other parts of the country might be puzzled when out here in the Northwest, Brandon, to see that. Most builders elsewhere have enough common sense not to do that, but it seems to be endemic out here. They are supposed to use some sort of a capillary break between the placed concrete and the siding and trim, and most do. However, though that satisfies the code bubbas, it won't keep rain from draining behind the capillary break, becoming trapped, and eventually rotting the siding and trim, and whatever is behind it, anyway. Last summer I had a house where that had been done on the south side of the house - the weather side here. Outside, the house looked great; inside the crawlspace behind that stoop, I could put a pick completely through the rim joist and siding, despite the presence of the capillary break.

I usually recommend that they seal the joint between the house and stoop with butyl. It can handle the different expansion rates of the concrete and the wood without the bond breaking. I don't think it will completely stop deterioration but I think it will probably greatly slow it down.

ONE TEAM - ONE FIGHT!!!

Mike

[Brandon Whitmore]

Mike O,

I'm happy to see that James Hardie has addressed this issue finally... now for the code folks to follow suit.

I usually shrug my shoulders when client's ask me how to fix concrete poured against siding (like at the steps). I just say it is a bad design and is often problematic, and tell them caulk is better than nothing.

The felt paper placed between the concrete and house wall is pretty much pointless from what I have seen.

[Jim Baird]

In GA the state amendments call for two inch clearance between paved surface and any wall cladding (except masonry) for inspection. We are in a heavy termite zone and pavement up against siding is where it they can easily get in.

[hausdok]

Originally posted by Brandon Whitmore

Mike O,

I'm happy to see that James Hardie has addressed this issue finally... now for the code folks to follow suit.

I usually shrug my shoulders when client's ask me how to fix concrete poured against siding (like at the steps). I just say it is a bad design and is often problematic, and tell them caulk is better than nothing.

The felt paper placed between the concrete and house wall is pretty much pointless from what I have seen.

Not only have they addressed it - they're enforcing it. Not too long ago, I had a situation where a builder's sub had poured a new stoop and walk directly against the Hardiplank. I called it out and the builder berated me, telling everyone that would listen that I didn't know my ass from a hole in the ground 'cuz there was a capillary break behind the concrete and the local code guy had approved it. I shot an email off to James Hardie describing the situation and promptly got an answer back from a fellow in their technical assistance department that not only was it wrong - they wouldn't warranty the product since it had been installed wrong.

A certain builder ate a little bit of crow over that one and his concrete sub came back, busted out all of that concrete and had to do it over again.

Wanna guess which major builder's developments I'm not welcome in? []

ONE TEAM - ONE FIGHT!!!

Mike

[Brandon Whitmore]

I just called out inadequate overlap on Hardi Plank siding-- it averaged 1 to 1.125" , and wrote up inadequate clearance from a deck to the siding (surface boards butted up against the siding-- the pic on their website clearly shows a clearance as being required).

I just had a builder get documentation from the manufacturer that says the installation is fine. I am still trying to get a copy, but the purchaser does have a copy. I happen to believe this builder because on the numerous other issues I wrote up in the report, he had 3rd party contractors come out and evaluate everything I documented, and had the new contractors make all necessary repairs (I am sure the original subs paid the bill).

It sounds like I will have to shoot off e- mails personally to their technical department to get verification on whether they will still warrant specific installations. It will be interesting to see what department the letter came from.

[Brandon Whitmore]

Carl,

What kind of siding was it?