pergola posts

[Rick Hughes]

SWMBO wants a Pergola built

Come up with suitable design ... assuming that I will be concreting in the

4"x 4" posts into the ground ....... as Pergolas I went to visit where they had used simply driven in metaposta were really shaky and unstable. (plus ground is full of stones so won't be able to drive straight)

If I concrete in the bottom 24" of the post, best I can come up with currently is make a former so that concrete is at least 3" above ground level, and chamfer top to facilitate water run off .... possibly make up some form of shroud or flashing around bottom of post, to 'neaten' things and again allow water run off.

Looked a at couple of books on Decking ... the recommendation there is not to concrete in posts, but to use 8" cardboard pier tubes, in a hole dug in ground, and finish 2" above ground, fill with concrete and push in a concrete post base.

Some of base types are here .... not sure what is available in UK

any ideas on this ?

[Nightjar]

I used oak, which was not a lot more expensive than pressure treated softwood, and stuck them straight into the ground. They are still sound

15 years later.

Colin Bignell

[David WE Roberts]

Metposts also do bolt down feet.

you could make your concrete post base then either let it cure and drill holes for bolts, or preferable cast studs into the concrete and then fit the base to these once the concrete is set.

HTH

Dave R

[David WE Roberts]

Also just seen they do a 'concrete in'.

[The Medway Handyman]

I've used them & they work a treat - with a big enough hole & enough concrete e.g. 2 bags of postfix per hole.

[The Medway Handyman]

Have a look at these

[Tim Lamb]

In message , Rick Hughes writes

Yes.

Don't concrete in or use anything which will retain water in contact with the post end grain.

I used 4"x4" treated softwood for ours and copied an installation I saw elsewhere. You need an *L* shaped piece of galvanised steel (they used stainless) with the long arm bolted through a slot in your post bottom and the short arm fixed to a concrete pad with a rag bolt or similar.

As has been said, diagonal bracing will make the structure rigid. Photo later if required. Current age 16 years:-)

regards

[82045]

4" x 4" is really rather light for a pergola. To be usuable it needs to have clearance underneath of about 7'. I'd recommend a minimum post size of 5" x 5".

[Tim Lamb]

In message , Tim Lamb writes

Photos here.

concrete pad is proud of the chippings because it was originally set in a lawn.

regards

[Gazz]

The fence at the bottom of our garden is shared between 2 neigbours, and owned by then, they both replaced the whole fence about 10 years ago, the one on the right had 2 posts, he concreted them straight in..... they have rotted through at the base and it's only the structure of the fence holding it all up,

The other neigbour had 3 posts, he too concreted them in, but he wrapped the bottoms of the posts in damp proof membrane, those 3 posts are absolutely solid, despite being the same age as the rotted ones, and the exact same wood from the same place, so pressure treatment was the same.

i'm in the moddile of building a shed and aviary, i've used damp proof membrane to cover the bottoms of the beams that are in contact with the concrete pad the shed sits on, so except for a torrential downpour flooding the pad, no water should ever make it to the beams, got my parents to do the same with their new shed, as the old one was 10 years old, and totally rotted underneath.

[Rick Hughes]

good point ..... it would also look a lot better

[Rick Hughes]

can you post a pic ?

[Rick Hughes]

I built a car port and did a similar approach .... had brackets welded up & galvanized, so that end of 6x6 posts sat on a support horizontal as well as slotted .

years on ....

bases were fitted with chemical anchors, 25mm off floor, then grouted in.

[Robin]

Just for my education, how do you cut neat slots in timber of that size please?

[Robin]

Just for my education, how do you cut neat slots in timber of that size please?

[Tim Lamb]

In message , Robin writes

Big circular saw bench with TC tipped blade, in my case. Tilt the post so the teeth cut parallel to the foot and just advance the work by the depth of cut you need.

regards

>

[Tim Lamb]

In message , Rick Hughes writes

Out there somewhere:-)

I think 4" is plenty strong enough. Aesthetically a heavier crosspiece might look better. My long runs are 4"x2" and the diagonal bracing at

45Deg. fits tight to that.

The trellis is B+Q finest fitted in alternate bays.

regards