Fixing and levelling Metpost Fixings? Job completed!

[owentaylor]

Hi all,

At the weekend I will be installing a 3ft high closeboard fence on top of my yard wall. The wall is 2' high on the inside and and around 3'6" on the outside and is in a fairly sheltered location. It is double skinned and made from pitched stone on the outside and 4" solids on the inside. The coping is made from indian stone and is about 1.5" thick and 45cm wide. It is bedded on a 1" thick layer of mortar and the wall was backfilled with mortar to about 1 course down. I hope this will give me a substantial fixing surface for whetever fixing I choose to use.

...which brings me onto my next question. I was going to use shield anchors but I have been advised by the fence supplier to use what they call 'Thunderbolts' (self tapping fixing that screw straight into pre drilled holes). They said that shield anchors may work loose in the mortar over time. Is this likely to happen? Does anyone have any experience of 'Thunderbolts' or similar types of fixing for this purpose?

Finally the Indian stone coping has an uneven finish - whats the best way of levelling the Metpost brackets?

Any advice is much appreciated!
Thanks, Owen

 

[Thermo]

your wasting your time and money with the met posts. youd be beeter running the posts down past the face of the wall and bolting them straight on.

 

[owentaylor]

Thanks for the reply.

There are a few reasons I didn't want to go down the route of running posts down the wall.

1. The outside is facing the street and posts bolted to the outside is a no-no. They wouldn't be in keeping and it would certainly raise complaints from the neighbours. The outside face is course 100 year old pitch stone. I would have had to use lots of spacers which would look unsightly.
2. The wall is a retaining wall which is very wide (almost 0.5m) and posts on the inside would really encroach on my space.
3. As the wall is low I wanted to use it as a ledge on the inside for seating/putting planters.
4. I didn't want to give people the opportunity to sit on a ledge on the outside, or leave their empty drinks cans/rubbish as they walk past.

Are Metposts really so bad? If they are fixed down properly, surely they will be suitable for a 3ft high fence. I'm using 4" posts.

You have me worried now...

 

[Thermo]

should be theyre crap, especially in that context

 

[owentaylor]

Thanks for the positive advice

I installed the fence as described. I bolted the metposts down with 80x10mm multi-monti fixings (basically drill a 10mm pilot hole then bolt the fixings straight into the stonework). Due to the thickness of the outer stone wall, the majority of fixings went through the coping, mortar and a good 20-30mm into the top coarse. I levelled the posts using M12 A2 stainless washers.

I was really surprised how well the fixings cut a thread into the stone and how tightly they bolted down. I will check them every few months but the fence is very sturdy. Also at one end there is a return on the fence and it is attached to a metal gatepost, further adding stability. For this job I really think the metposts were an ideal solution, although I wouldn't recommend using them for anything higher.

Here are some finished pictures. The fence, along with the copings look a bit new at the moment but once they weather I think they will blend in well. Any comments/criticism welcome.

edited to fix broken image links

 

[JohnD]

that's great, will you post some more pics please after you've had some windy weather?

 

[owentaylor]

Yeah sure

In all seriousness I don't think I will have a problem. As you can see I'm surrounded by houses so I'm in a sheltered location. The metposts are bolted through the coping and into the first coarse of stone. The wall is very substantial (100mm solids on inside, cavity filled with mortar/loose stone). I really can't see a 3 foot high fence taking off 11m of coping and a whole coarse of heavy stone.

But then I may be wrong...touch wood!

 

[WabbitPoo]

I am dubious too, but I have to say its a very nice looking job. U must be well pleased.

 

[owentaylor]

Thanks yeah I'm really pleased with the outcome, especially as it is my first project of this kind and it only took me a day (plus an hour the evening before spraying the metpost brackets black).

Just have to point the old section of wall, render the wall on the inside, finish off the stone flagging, and install some gates...then I can put my feet up for the summer.

I'll be sure to post here if the fence comes down in the wind.

 

[WabbitPoo]

what did u bed your driveway slabs onto?

 

[owentaylor]

Laying the flagstones was a bit of a pain as they were all different thicknesses ranging from 2" to 6". They came out of the middle room in the house and I wanted to make use of them.

I went over the whole area with a wacker, then spread about 1" of MOT then wacked it again. The flags were laid on a strong mortar mix of 3 to 1 and were lifted to ensure high coverage and then I buttered up the edges as I went. Due to the variation of thicknesses, some flags are laid on about 4-5" of mortar. I know this isn't ideal but I made sure to position the thicker of the flags where the car will drive so there is less mortar here.

Finally I left them to set for a good few weeks before pointing them and then a further week before driving on them. They seem ok so far.