Roof cap flashing to cover old flue hole

Forums › Home Workshop DIY › Roof cap flashing to cover old flue hole

adam1979

1 post

Wannabe Geek

#147350 16-Jun-2014 21:36

Hello,

I have just removed a wood burner flue from my roof and now need to patch up the hole left behind. Can anybody tell me where I can buy a 400mm wide cap flashing from? I have tried all the obvious places like bunnings and my local builders merchant with no luck.

In the photos you can see that the hole is currently sealed with a flowerpot. It's survived a couple of big storms so far with a rubber sheet over the top held down with bricks! The type of cap flashing I need would be exactly the same as the 400mm one behind the flowerpot in the photo but a little longer to extend over the hole. No idea where I can get hold of this.

Cheers

Adam

Coil

6614 posts

Uber Geek
Inactive user

#1067067 16-Jun-2014 21:40

Jeez! Is that a ceramic pot??
I would suggest that you put in new Tin across the area and save having joins.

mattwnz

20163 posts

Uber Geek

#1067112 16-Jun-2014 22:17

I think you need to get a new piece of steel, and under flash it under your existing steel flashing. If you look at the the NZ building code, it will show you the type of flashing you will need. But a roofer is probably needed if you can't do it yourself. They will remove that flue flashing sock and overflash it with a steel flashing.

Dynamic

3867 posts

Uber Geek

ID Verified

Trusted

Lifetime subscriber

#1067127 16-Jun-2014 22:28

+1 for a new sheet of iron

We have used these guys twice before very successfully on 2 different roofs: http://www.aucklandroofrepairs.co.nz/

“Don't believe anything you read on the net. Except this. Well, including this, I suppose.” Douglas Adams

Referral links to services I use, really like, and may be rewarded if you sign up:
PocketSmith for budgeting and personal finance management. A great Kiwi company.

MikeB4

18435 posts

Uber Geek

ID Verified

Trusted

#1067134 16-Jun-2014 22:32

You could nail (lead head) some sheet lead flashing one the hole

Coil

6614 posts

Uber Geek
Inactive user

#1067136 16-Jun-2014 22:35

KiwiNZ: You could nail (lead head) some sheet lead flashing one the hole

Hmmm. I would suggest just doing the whole sheet instead messing around and causing leaks or future issues.

Such brainwave occurred!

eracode

Smpl Mnmlst
8860 posts

Uber Geek

ID Verified

Trusted

Subscriber

#1067223 17-Jun-2014 02:09

KiwiNZ: You could nail (lead head) some sheet lead flashing one the hole

How would you stop water running in under the lead? I think this is one of those "worth doing, worth doing well" situations => new sheet of roofing as suggested by others.

Sometimes I just sit and think. Other times I just sit.

DarthKermit

5346 posts

Uber Geek

Trusted

#1067226 17-Jun-2014 02:19

What area do you live in? You might be able to have a custom flashing or full length of roofing iron made to the existing profile if you have a roofing or sheet metal type company in your area.

Whatifthespacekeyhadneverbeeninvented?

Sharesies

Trade NZ and US shares and funds with Sharesies (affiliate link).

kiwitrc

4123 posts

Uber Geek
Inactive user

#1067231 17-Jun-2014 06:01

As Dynamic says above, get a roofer to replace the sheet with a new one, including roof underlay. This will most likely be cheaper than getting a flashing made to match colour etc. Also if you decide to sell a flashing is going to raise questions and invite closer examination.

gazbo

89 posts

Master Geek

#1067233 17-Jun-2014 06:19

Rangitoto is in the background so try Monaghans. You need a coloursteel flashing if further than 1km away (need .55g with a coating suitable for seaspray if within 1km of the sea as a bird flies) as per above the penetration to lap under your existing flashing and run it over the penetration and give it a 200mm minimum cover. If building from new you need a minimum 10 degrees roof pitch for this detail if you wish to comply with E2/AS1. If you don't have 10 degrees which looks likely, just buy a flashing that runs the entire length from low to high points, lapping over the roofing to the gutter and lapping under your high point flashing.

flashingfabricators.co.nz

I have had contractors use them many times on jobs I have managed and they do good work.

Also remember that E2/AS1 is not the only solution. What you propose is fine as long as there is adequate support either side of the penetration. If there isn't it will dent easy in which case you may wish to use powder coated aluminium 1.2mm thick or simply install some blocking for support.

kiwitrc

4123 posts

Uber Geek
Inactive user

#1067234 17-Jun-2014 06:41

Check this out, there is a guy here who knows all about roofs. http://www.geekzone.co.nz/forums.asp?forumid=141&topicid=138475

Edit: Ha ha, Gazbo as above is the guy, sorry should have re loaded the thread.

MikeB4

18435 posts

Uber Geek

ID Verified

Trusted

#1067238 17-Jun-2014 07:11

eracode:
KiwiNZ: You could nail (lead head) some sheet lead flashing one the hole

How would you stop water running in under the lead? I think this is one of those "worth doing, worth doing well" situations => new sheet of roofing as suggested by others.

When we replaced our gas hot water with an Infinity the hole left in the roof was repared I this manner by a roofer andvitvhas never leeked, that was done circa 6 years ago.

Bung

6486 posts

Uber Geek

Subscriber

#1067252 17-Jun-2014 08:14

If it's Colorsteel you don't want any lead touching it. Basic rule.

MikeB4

18435 posts

Uber Geek

ID Verified

Trusted

#1067257 17-Jun-2014 08:53

Bung: If it's Colorsteel you don't want any lead touching it. Basic rule.

Zinc will be OK but it will eventually need replacing due to galvanic effect.