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mattdonnakelly
15th November 2005, 10:18 PM
Hi , Could Someone Advise Me Of The Best Way To Attach A Pergola To Your House.

We Are Looking At Building One, But That Is Our Only Issue.

We Are Building A Gable Pergola Attached 1 Side To House And 1 Side To Garage.
The Roof On Our House Is Colorbond

Wood Butcher
15th November 2005, 10:49 PM
Unless you can get some sound advice from a structural engineer don't. I installed a shade sail to a house years ago screwing the fixing points directly to the roof trusses (was what the owners told me to do). During a really big storm later the shade sail was removed by the winds taking some of the roof with it. The insurance company would not cover the damages because the fixing points were not approved by an engineer.

This is not to say that there is not a way to do it, but always cover yourself in case the worst happens!!

Trav
16th November 2005, 12:24 PM
Rowan is dead right. Screwing into, say, the fascia boards is a good way to have part of your roof removed in a big storm. Get the book by Alan Staines on decking and pergolas. It's available from Bunnings - it can be a little confusing at first, but it tells you what you need to know.

It really depends on whether you are going to put a roof on it or not. If no roof, you are probably OK. If you are going to put shadecloth or laserlight stuff on it, you'd want to make sure that it is structurally sound.

Get the book - it is a really useful book if you are thinking of doing this kind of stuff.

Trav

Bodgy
16th November 2005, 01:09 PM
As said, it's all about the roof. No roof and even our bloody council (consistently worst or runner up in NSW) exempt them from development aprrovals, provided they are not over a certain size.

I think you really need to be more specific. Post a sketch with dimensions. If its just a small thing, with no enclosing roof, then you'd probably just bolt the top plates to your adjoining house/garage wall.

If you want design ideas Google 'Pergola'

rod1949
16th November 2005, 01:29 PM
Your can get flat bar (varing lenghts) with a bolt welded on one end at an angle (try Bunnings). The flat bar is bolted to the rafters of the house with the bolt on the end coming through the Fascia. You can then bolt the plate for the Pergola rafters to sit on.

MrFixIt
16th November 2005, 02:09 PM
Hi

Like most things we build, it requires some common sense in installation methodology.


Unless you can get some sound advice from a structural engineer don't.

Unless you are a beginner or not too au fait with such things as building pergolas then maybe that advice is required. I have built many pergolas over the years and never sought the advice of a SE. None have collapsed or failed in any way - (though a subsequent owner of our first home decided to use the 4" x 2" battons/decking to feed their wood heater :eek: ).


I installed a shade sail to a house years ago screwing the fixing points directly to the roof trusses (was what the owners told me to do). This was a silly thing to advise and to do. It would be TOO much to expect that a single (or even two) fixing points on the roof trusses would hold the wind power of a "driven" sail!


During a really big storm later the shade sail was removed by the winds taking some of the roof with it.An obvious result and should really have been expected.

To fasten a sail to the roof of a house would require something such as a 4x2 that spanned a number of roof trusses (IMHO) at least EIGHT trusses and then fasten the sail to THIS 4x2.

Fastening a pergola to a house requires a similar number of fastening points. If you have exposed rafters as my house does then the fitting is easy, using the appropriate pergola mounting brackets.

If you have boxed eaves and especially with the metal fascias, you NEED to have the brackets that can be bolted to the rafters and have a threaded rod that protrudes through the metal fascia. The threaded rod is then used to fasten a 4x2 to the front of the fascia.

Be aware though that most metal fascias do not necessarily have the rafters directly behind them. Bolting a 4x2 to such a fascia may cause some distortion of the fascia. It would be prudent to check for this and perhaps provide "packing pieces" where necessary to keep the fascia "straight" when the 4x2 is fastened TIGHT :D

From this 4x2 you can then fasten your pergola rafters by your preferred method. The rafter hangers are the easiest, though somebody on this list derided users of such devices, maintaining that the *real* way of doing this is with proper housing or lap joints. Hmmm? That's up to you :D

Local councils requirements seem to vary. One council said I could build a pergola attached to the house if it was not covered (eg tiles/tin etc) battens were ok. Another council required drawings and approval for just having it attached to the house.

If in doubt, provide MORE fastening points.

The last pergola I built, here at home, has alsynite mounted directly on the rafters, over this is 50% shade cloth and on top of all of that are 2x1 battens. So I have a weather proof pergola that has 50% shade of which that has 50% shade cloth covering. It works VERY WELL for us :D

BTW the guys supplying the Alsyite said "you can't install Alsynite like that" (under battens) - watch me :D :D

ThePope
16th November 2005, 03:25 PM
Unless you can get some sound advice from a structural engineer don't. umm...he's building a pergola WB, not the harbour bridge mate :)

What are you attaching to mattdonnakelly:

the wall of the house, brickwork or timber frame ?
or
the fascia, timber or metal ?

and what's the approx size ?



The last pergola I built, here at home, has alsynite mounted directly on the rafters, over this is 50% shade cloth and on top of all of that are 2x1 battens. So I have a weather proof pergola that has 50% shade of which that has 50% shade cloth covering.
Can't for the life of me figure it out so gotta ask, what's the theory behind doing it ass about MrF.

Wood Butcher
16th November 2005, 04:39 PM
umm...he's building a pergola WB, not the harbour bridge mate :)
I do realise that http://www.ubeaut.biz/ohreally.gif, but having being involved with many different scenarios patching up dodgy work (ie. because of the twits that previously owned my house) I have been advised, especially by my insurance agent, that you should always cover all of your bases.

Most councils would require you to submit an application for building or adding to an existing structure with detailed plans anyway, which you may need you may need to have engineers approval for. The council were I had my last house required that anything with a floor area of 10m2 or over needed council approval.

MrFixIt
16th November 2005, 06:13 PM
Hi


Can't for the life of me figure it out so gotta ask, what's the theory behind doing it ass about MrF.

Hmmm? A logical question I guess :D

I already had an existing pitched roof pergola covered in battens, with the shade cloth underneath. The pitched roof pergola does not look nice (IMO) with the shadecloth on top of the battens - hence I placed the shade cloth underneath.

I now wanted to remove the small (original) flat roof pergola and replace it with a matching pitched roof version. The two pergolas are almost at right angles to each other and need(ed) to match in appearance. As we also wanted it weather proof (well, waterproof) I decided to cover the small pergola with Alsynite.

Due to the requirement of a matching battened appearance and not wanting the pitched roof to look like an Alsynite pergola, the Alsynite was therefore placed under the battens.

Both pergolas now look the same externally, yet the smaller (newer) pergola is waterproof. It is very discrete and people do no notice the Alsynite unless it is pointed out to them - or it rains and they don't get wet :D :D

BTW both pergolas have an unsupported span of 8+ metres and use a 180mm x 75mm "C" channel to span the distance.

I did have an engineer work out the "C" channel size requirements for me. He said it would droop about 25mm in the centre and he was spot on :D

I have some pics somewhere if you need/want to see it.

A previous pergola I built (on my last home) was a deck to the second storey (I built) and a pergola from the ground floor. This was made with 4 x 2 "battens" with a 25mm gap between each batten.

As the battens were more or less placed in a north-south direction, we had 100% shade for most of the day and still had 80% shade during the hottest part of the day. Plenty of light space surrounded the pergola so it was not dark, just shaded :D.

HTH

ThePope
16th November 2005, 06:46 PM
Ok, it's just you prefer the appearance of it that way. Unorthodox to be sure but as long as it works.


I have some pics somewhere if you need/want to see it.
Yeah sure, whack em up.

dazzler
16th November 2005, 08:24 PM
Hi Matt

If you it is an unroofed pergola, made of oregon or similar weight timber, my experience is that the U shaped pergola brackets sold from bunnings screwed or nailed into the facia will be fine.

This of course depends on the spans but they seem fine up to about 3.6m IMExp.

If its gonna be roofed then it needs to be more securely mounted.

In this case I have always dynabolted a 5" x 1 1/2" board into the brickwork just below the eaves at 300 centres and then bolt the brackets to that.

The other thing is if you live in a cold climate I reckon it is really great to grow a wisteria over it so that you have shade in summer and sunshine in winter. Plant it so it grows up the posts and it will also help to secure it.

Have fun.

dazzler

Bodgy
16th November 2005, 08:55 PM
. The council were I had my last house required that anything with a floor area of 10m2 or over needed council approval.

Only if you tell them

Trav
17th November 2005, 08:40 AM
Only if you tell them

Or if you sell your house! :D

TP

Bodgy
17th November 2005, 09:01 AM
Or if you sell your house! :D

TP

To a council building inspector?

meerkat
18th November 2005, 10:04 AM
two things ...

Check with the council and their guidelines and 2 like Rowan said don't risk it get some professional advice. It may cost a little but it beats the alternative.

Andrew

MrFixIt
20th November 2005, 02:12 PM
Ok, it's just you prefer the appearance of it that way. Unorthodox to be sure but as long as it works.

Yeah sure, whack em up.
Pergola pictures as mentioned...
the first photo shows the Alsynite lined pergola above the outdoor setting, the photo was taken from under the original pergola.

The second photo shows the original pergola taken from under the Alsynite lined pergola. I you look closely at the roof of this pergola you can make out the clear Alsynite.

The last photo shows a reasonable view of both pergolas. You can probably see that the original pergola covers approx 2.5 metres of the pool, great in summer :D

Though these photo's do not show it, the pergolas' battens are "raked back" over the existing tiled roof so that it looks more like a "built in" pergola than something just "tacked on" to the house :D

(I had to make the last file a little smaller for it to fit the 100kb upload limit)

Johnny-DIY
30th January 2006, 10:14 AM
Anyone experienced putting in one of those fancy pergola's from Bunnings? It's sort of a hexed shaped setup with three guard rails and a stage sectioned shade cloth cover ... currently cost around $399 for DIY.

I'm thinking of getting one but am not sure of the best way to secure it because I don't want the wind to shred it to bits, we do getting pretty bad wind in Melb. My yard is paved but the pavers are not concreted in so securing it to a paver I suspect won't help much.

Based on the specs on the box the whole key weighs only around 42kg so I don't think will hold its own against strong wind. Have anyone else found otherwise (perhaps because of the 2 staged cover that may be designed not to catch th wind so much ??). Any tips on ways to secure it would also be appreciated.