PDA

View Full Version : Help needed for a fence.















ComboSquare
17th August 2007, 03:53 PM
Hi, I'm building a fence on Monday, and was originally going to use 90x90 treated pine posts and 70x35 t. pine railings.

Quick questions:

1) I'm not sure whether or not the railings are too small though? (Distance between posts is around 2.6/2.7 metres). Will they sag in the middle? I'm attaching corrugated iron to it. Fence is around 2.8m high (incl 500mm trellis).

2) If I used larger material for the railings, such as 90x45...would that cut too much into the posts (half)? I know for a birdsmouth for a rafter you're not supposed to cut more than 1/3rd of the way square into the timber...

3) Is 90x90mm the correct choice for fence posts? Lots of fences seem to use different dimensions?

Cheers in advance...

Combo.

Colin Howkins
17th August 2007, 10:20 PM
Giday Combo,

90x90 I reckon is Ok for the posts. I think 70x35 for the rails may be a bit light. Got a fence similiar myself, the rails are 90 x 35. But it is all hardwood.

Besta luck

Colin Howkins
Graceville Qld

mic-d
17th August 2007, 10:28 PM
Hi, I'm building a fence on Monday, and was originally going to use 90x90 treated pine posts and 70x35 t. pine railings.

Quick questions:

1) I'm not sure whether or not the railings are too small though? (Distance between posts is around 2.6/2.7 metres). Will they sag in the middle? I'm attaching corrugated iron to it. Fence is around 2.8m high (incl 500mm trellis).

2) If I used larger material for the railings, such as 90x45...would that cut too much into the posts (half)? I know for a birdsmouth for a rafter you're not supposed to cut more than 1/3rd of the way square into the timber...

3) Is 90x90mm the correct choice for fence posts? Lots of fences seem to use different dimensions?

Cheers in advance...

Combo.
The sizes are OK-the corro will help support it. Don't checkout the posts for the rails, just screw the rails to the face post with 75mm batten screws - faster and will minimise water rot.

Cheers
Michael

rgum
18th August 2007, 01:28 PM
Originally 9o x 9o posts ? Well if you do... don't check out the posts. As said, fix the rails to the post face. The iron sheets will be great support in preventing any sag.

Posts are nearly always, In Vic, 2.7 centres. You can mov'em around if a situation requires it.

Rail thickness ought to be relative to the post thickness.
Having only half post thickness left after / in the Chkouts,.. will impeade on the strength integrity of the post and its ability to provide you with a long service.

Allow for the thickness of the rails in setting back your stringline for post line up. Run only one string line. Bout 4 to 5 inch off the ground.
Pick your best two, straight posts for a starter and a finisher post.

Suggest....75 x 125 posts. Cypress is better than treated crapiata. Rails.....5o x 75. They can be checked in.
If you need checkout templates give us a bell.

Cheers.....Tony. :2tsup:

echnidna
18th August 2007, 05:05 PM
The normal size for fence posts is 125 x 75.
This gives adequate strength after checking rails in.

The rails should be 75 x 50 or 70 x 45.

ComboSquare
18th August 2007, 07:27 PM
Thanks for all of your responses. One of the reasons I was going to use 90x90s was there is an existing post there at those dimensions. Also, it might be difficult to use 75x125s because there are two sides to the fence which join at a right angle. If I checked into the posts at the corner post, then there'd be hardly anything left of the corner post where the railings met! I know this is sometimes the case for the top of posts, but surely not halfway up a post?

I had purchased 12 lengths of 70x35mm railings, now I'm not 100% whether to return them and get either 90x35 or 70x45 timber for this purpose.

But I'll be screwing to the face of the posts after these recommendations.

rgum
18th August 2007, 07:44 PM
Combo. get in touch via PM.

Cheers. :2tsup: