# OT: Installing a Fence into a Tarmac Drive.



## wizer (28 Apr 2005)

I have posted about this on the 'Ask The Trades' forum but discussion is slow forthcoming. 

http://www.askthetrades.co.uk/cgi-bin/y ... 1114603124

I just wondered if anyone here had any comments on this. I have arranged a couple of quotes for the work, but know from experience that fence installation is reasonably expensive and I 'think' I can do it myself.


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## RogerS (28 Apr 2005)

WiZeR

What sort of base is the tarmac on? How far are you going to extend the fence? If it's only 10' or so then lump hammer and chisel will be cost effective but tiring.

If it's a long way (and only you can be the judge of that) and the tarmac is on a base of stone then using some sort of breaker to get through will save you a ton of work. Can you run power there for an electric one? A medium size breaker will probabl;y suffice.

If you're using concrete then make sure you have some sort of temporary holding for the posts while it sets.

Or you could use those metal post supports (metpost or similar) but they are expensive in quantity. But if it were only 5 or 10 then I'd probably go down that route rather than go through all the hassle of getting in sand, aggregate and cement and mixing up the concrete. Unless you've already got it in :wink: 

Hope that helps a bit

Roger


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## OLD (28 Apr 2005)

Try a sds drill with suitable flat and pointed chisels i used one to demolish a strong wall recently no problem buy (screwfix) or hire .


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## wizer (28 Apr 2005)

thanks guys

The fence will run up the drive about 8m. I am yet to look into fence products. I had a quick look on the B&Q website and saw these http://www.diy.com/diy/jsp/bq/product/product.jsp?CATID=8050163&entryFlag=false&PRODID=8021808 panels. (H) 1.8m x (W) 1.83m So I would need 4 panels plus 2 for the connecting fence and 2 gates. 

I am unaware what is under the tarmac. Judging by the poor way in which this house (circa 1999) was built, i'd guess builders rubble, concrete and mud. 

Roger, can you tell me a bit more about those metal posts? Do you mean the metal spikes with a square top to seat the post?

I'm more geared up for doing this myself tonight as the tradesman that I arranged to give me a quote has decided to NOT turn up and not call!!


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## wizer (28 Apr 2005)

i have been looking into metpost, seems like a good product to use. However whilst looking I found this: http://www.screwfix.com/app/sfd/cat/pro ... 6&ts=10236
Do you guys think screwing these into the tarmac would be a sturdy solution?


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## RogerS (28 Apr 2005)

Yup...something like this
http://www.screwfix.com/app/sfd/cat/pro.jsp?id=56843&ts=10202

You need to make sure that they are the same size as your posts...sorry, grandma :wink: and you may get cheaper elsewhere on the web.

As it's only 8m I don't think I'd bother with concrete as you've only a few posts to do...funds permitting, of course. Also, I'd chisel out a bit of tarmac, stick an oddment of wood into the top of the metal thingy (wood long enough to put a level against it) then try whacking the spike in ...you may be lucky and that it forces it's own path...then again, you may be unlucky and find that stones, whatever underneath force the metal thingy out of alignment :twisted: 

If it was really full of stones etc then chipping out a reasonable size hole and using concrete might be the only way to go ...the metal psts really only work well through soil IMHO. Why not have a few investigative pokes with a cold chisel to see what's underneath?


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## wizer (28 Apr 2005)

thank you roger, looks like this weekend I are be mostly drilling tarmac :shock: :wink:


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## Shady (28 Apr 2005)

Beware the 'metpost'/'easypost' option... 

Speaking from personal experience, they almost invariably twist/warp as you hammer them in (even if they're plumb vertical, which they won't be, they hit a stone or brick and twist 'out of line') - just enough to introduce noticable bendyness to your spanking new fence line. And once in, they're 'unremovable' unless you do some serious excavation.

Despite the apparent increase in effort, I would suggest that digging a suitable hole and filling it with appropriate cement mix for the fence posts will give you a much more 'professional' looking fence for very little more work- if any.


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## kityuser (28 Apr 2005)

I would suggest 100% against metposts.

having laboured for around 6 years for a tree surgery and fencing company, I`ve had some real onsite experience with these things and they are REALLY NAFF!
They twist, bend, split and basically never end up where you want them.
............. in the middle of a clay soil field.... perfect, however in a driveway - forget it!

I`d suggest (to get the best job), that you cleanly cut the tarmac with a grinder, then gun out the hole (with as stated, a medium breaker), install the post, use "postcrete" from Wickes (blue circle) is FAB stuff!

1) dig the hole
2) fill with water
3) position the post
4) pour in "postcrete" bag
5) stir
6) wait 5-10 minutes........

The stuff goes off Very quick, and hardens like readymix 8) 

Instant fence!

leave the concrete below the tarmac level, then backfill with "instant tarmac" again from wickes.

We did this on several jobs with total sucess!, you won`t believe how good you can "make good" the tarmac again.

note: for wooden posts, don`t forget to slightly raise the tarmac around the post to stop water collecting and causing premature rot.

good luck

steve


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## wizer (28 Apr 2005)

thanks kityuser, that was my first method in mind.

Couple of questions.... How deep should the hole be? Should the fence post be layed directly into the hole/crete? or protected in some way? What sort of clearence around the post should there be? As little as possible?

When you say cut the "tarmac with a grinder"  what do you mean by breaker? and by medium grinder, is this http://www.hss.com/Fae.asp?sysPage=wsHo ... sLanguage=[BASE]&resetToGroup=YES ok?

ok, that was more than a couple of questions :wink:


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## kityuser (29 Apr 2005)

sorry for the lack of detail! 

what I ment by "cut the tarmac with a grinder" was this: 

you are aiming to have a clean cut square in the tarmac with a hole in the middle for the post to be concreted into. The cleanliness of the tarmac extraction means that it is much easier to "make good" with the instant tarmac at the end and thus give you a better looking job. 

the "medium grinder" was an indication that you need a cutter disc that is capable of cutting thru the tarmac depth i.e. a small disc may not be able to cut deep enough. 

by "breaker" i mean the power tool used to excavate the hole (if concrete of stone is present). I`d suggest 2 levels of tool: 
1) an SDS drill fitter with a pin or chisel 
2) a "KANGO" style hand-held breaker gun 

i.e. http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 01304&rd=1 

ask at any hire shop for a "Kango", they`ll know what you mean. 

HOLE SPEC: 
***************** 
usually for a good quality job you should always concrete the post into the ground AT LEAST 18" deep, most of the time we would go 22-23 inches. 

However more important is how the hole is dug (sounds stupid does`nt it!), you want to aim for a nice round hole with around 3.5-4" of clearance all round the post (when its dropped into the middle). When its concreted in you are aiming for maximum support from the ground around the post with the concrete merely there to hold it in place/upright. 

Digging a massive "bomb" crater achieves nothing/wastes concrete and in the end produces posts that can easily be knocked over/blown over. The posts generally tend to rock on the massive "lug" of concrete (just like a self-righting toy). 

You can try to treat the bottom of the posts (if they are wooden), but generally whatever you do the water is going to lay on the ground and rot the post where its concreted in (i.e. concrete is`nt permeable so the water collected around the post). 
However you can minimise this by: 
1) concrete the hole right to the top (leave 2 inches for the instant tarmac) 
2) instant tarmac around the post, raising the level in a slight slope up to the post. 

hope this helps 

steve

ps I`ve just done the FIRST fence for MYSELF *woow*, after years of doing other peoples (neighbours, relations, friends and work)

if somebody wants to host a few of my piccies I`ll get a few taken.


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## wizer (29 Apr 2005)

kityuser":2uzbyzga said:


> ps I`ve just done the FIRST fence for MYSELF *woow*, after years of doing other peoples (neighbours, relations, friends and work)



Don't want to pop round and do mine then do you? :wink:  

Thank for that, I think I have all the info I need to do a good job. Now to spec up the equipment I need....


send the pics to wizer @ wizer .co.uk if you want me to host them


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