Timber gate posts

[HappyBudda]

Hi folks,
Bought a timber gate from a chancer in the local paper for i think £450 (old money) a few years ago. First sign of a bit of wind brought the whole thing down, wall and all. Thing is he i have an gate entrance of 17ft wide and the guy put heavy wooden gate on 4 inch posts which he did not sink into ground, just bolted to stone wall cladding.
In the meantime i have bought 8inch posts about 8 foot in height.
Questions:
1. How deep should i go with my gate post holes
2. Best way to dig through ground
3. Best ratio for cement mix as do not want too much pressure put on walls.

Any suggestions appreciated

 

[Pique318]

Is this a 17ft gate or 2 x 8.5ft gates ?

Either way, I'd go for iron posts...timber is fine for shorter distances but that gate is probably very heavy and will put a lot of stress on the post.

 

[osuldo]

wondering where is the best plase in cork to but stud rail and large timber gate posts would railway sleepers do as gate posts
many thanks

 

[HappyBudda]

Pique318 :Thanks for reply, Its 2*8.5 gates i'm using existing gates but taking every second rail off to lighten so not as heavy as before.

osuldo:was that an answer or a type of thread-hijack?