ilyaz

We want to make our existing concrete patio bigger. However, we're also thinking that in another couple of years we might want to big addition which would include removing the existing slab altogether. So we're not looking to put a larger concrete slab in. At the same time, since the "couple of years" might stretch to 3 or 4 or 5 and further, we're looking for a solid way of adding to the existing slab so that what we end up with does not fall apart I a year or two.

As you can see from the photos, the patio has two large trees (+ some PITA bamboo) on one side and slopes down on the other sides. Ideally, we would probably want to expand the patio as close to the trees as possible and then add another couple of feet on the other two sides.

What sort of solution would recommend for this? How close to the trees do you think we might get? Thanks!

nealtw

Not sure of measurements, but I would look at building a wood deck right over the old slab and extend it bigger as you like. With some fancy framing you could build really close to the tree, in a way that you could make the hole bigger when the tree grows. I don't think I would do it in stages.

Wuzzat?

Or you could extend the slab in several directions by 'framing' it with landscape timbers flush with the slab surface.
It might look like it belongs there, like a picture frame.

BridgeMan

To answer your original question--a good way to kill any tree is to place an impervious barrier (plastic, concrete, etc.) under the drip line area. Doing so deprives the roots of oxygen that they need. With trees as large as yours, stay at least 5 or 6 feet away. Of course, a wooden deck is a different matter, and can be built within a few inches of the trees' trunks. Expect to encounter serious roots when excavating for the deck's footings, though.

frankflynn

Cement pavers - something like a tile but typically 2"-4" thick.

You might be able to find some free off of craigslist - or buy them. Cheapest is to just add the ares you want with free ones, next step up would be buy ones that match the existing concrete and for a really nice look rip out the patio and replace all with pavers.

The advantages are: easy installation (no more work than poured concrete) but super easy removal and you can reuse them later - if you do add on you might want a different patio and you can use the same ones. You can make almost any shape with them although it's far easier if you don't need to cut them.

They can go right up to the tree (you will have to remove the surface roots) - they allow water to pass between them and soak into the ground so the trees will still get water and you don't have to worry about pooling in your yard.

And if after your new addition is done you can give them away for free (might be able to sell them - but let's not get greedy) that would save you some $ from not have to dump them.

The traditional installation is to remove the dirt and to frame the area with some kind of 2"x4" (that can take being in contact with the dirt) add an inch or two of sand to make it easy to level. Then put the pavers down so they are all level and snug then put some sand on top - sweep it around so it fills the cracks and you are done.

Should you not get to your addition for 10 years or so and the tree creates some bump in the pavers you can dig out just that area and re-level just that spot.

Good Luck,
F