How to get 20 years out of 150mm timber posts

[Bouba]

SORRY GUYS(i am not shouting) thanks everyone for the helpful advice.
Confusion was with the weight of gates. I am a moron. Basically both gates weigh approx 94 kg (47kg each).Would this make a differencenow to the scenario.

 

[JohnD]

the lintel need not be as big as the posts. I've used a piece of decking timber, which is substantial enough not to look "mean" and is I think about 35mmx120mm or thereabouts, bolted through the top face of the posts.

I like to fix wooden posts to concrete spurs, so you can easily unbolt the posts if they rot, but as you can space them above the ground, they won't, easily. You need a rain cap on the top as well. I soak top and bottom in Cuprinol Green (may now be unobtainable, so try Clear).

For what you originally described, I would have used steel. What you are describing now is more like a substantial wooden door, so a frame with top member would, I think, do. I have done something similar with 78" high gates. Without a lintel, they would lean.

 

[Bouba]

John. Thanks so much. Really appreciate it. I will be using 150x50mm as a lintel. I like your idea of concrete spurs. Just trying now to locate if they do it in 150mm size.

 

[JohnD]

for heavy loads, I have seen people use two spurs, with the wooden post slotting between them. You can use threaded stud. You might be able to get stainless. I use stainless acorn nuts when they are on display, but the stud must be short enough to fit. Long stainless bolts in large sizes (10mm, say) are quite expensive. Galvanised stud and nuts that have been outside for a few years will rust together.

oldun has done more of these than I have, so he may have a better idea.