How to bolt a fence post to a wall

I had better cover this topic because it comes up quite often.  If, for example, you want to start the new garden fence at the house and work away from there, it's not always possible to dig out and set a post in concrete right next to the house or building.  That's because the building foundations are right there and you might only get down a foot or so before you hit the concrete.  A foot deep is not enough depth to adequately secure a fence post. On top of that, the building utilities, pipes, cables and drainage systems are all usually placed in close proximity to the building, so you could discover them when you dig down, and it is against the law to pour concrete on top of utilities, so that is not an option.

What you are left with is to bolt that first post to the wall instead.  Don't worry, it's not difficult.  You'll need a good drill and some wall bolts but I'll show you what they are and where to get some.

I use Thunderbolts for this job.  these are simple coarse thread masonry bolts so there's no need for rawl plugs or inserts.  You simply drill through the post and into the wall until you are deep enough and then screw in the Thunderbolt until it's tight, and that's it, job done.  I usually put three in, top, middle and bottom.

For securing a 100mm post to a wall , I would choose a 150mm M8 Thunderbolt and drill a 25mm recess in the post to give 75mm of bolt in the post and 75mm of bolt in the wall and that never let me down.  You could hang a landrover off that post once it was bolted up.

Here they are here.  They come in a lot of other sizes and diameters too, but the M8 150's were always my favourites. 

Occasionally, we would be asked to attach a fence along the entire length of a low wall, to add security or privacy, and these bolts are exactly what I would use to do that job too.  The setting out process is the same, I would set the first and last posts to the desired height and then run a string line along to guide the positioning of the remaining posts until they were all in place and then build the fence as normal.

Here's one we did for the church neighbours. Churchgoers are a right rowdy bunch who make far too much noise on a Sunday morning lol

I had better say, it helps if the wall you are bolting onto is nice and straight, but that's not always the case.  If there are slight deviations then you can insert wedges or packing blocks depending on the severity of the problem.  I would then make sure to drill through the wedge so that the thunderbolt is holding it in place and it doesn't ever come loose.  The other alternative is to shave some material off the post to bring it into level, but that only works if it's a really slight amount.

So that just about covers the majority of things to do with setting posts, so now it's time to start building the fence onto the posts.  See you on the next page.

How to build a fence once the posts are set.