Vertical Flue issue

[Guzzles]

Hi,

I am having a vertical flue fitted with my new boiler next week. Before you all ask, the plumber is Corgi registered. My only concern is his approach to fitting the vertical flue. We have a tiled pitched roof, and he is providing a Vaillant Vertical Flue Kit, with associated tile flashing kit. When I asked how he will cut through the underlay felt, he said that he just cuts a rough hole and makes sure the felt is left 'pushed up' so avoiding any water coming in. He said that the felt isn't really required, so leaving it like that isn't an issue. Now I may have mis-interperated him, so please don't get too upset about the bloke.
What I would really like is to find out what other fitters do the the felt in this situation as presumably you want to make it fairly air tight to stop water/dust/insects etc entering?

 

[simond]

The Vaillant adjustable slate is a pain to fit with plain tiles.

We always sub out any roof work to a roofing professional because that is his day job. His van holds slates, felt, tiles, just like plumbers have copper and fittings. So there are very few insurmountable issues, and no-one bodges. Talk to boiler installers -they LOVE vertical flues .

It also avoids accidents with our installers, who are too valuable to lose off a roof .

It costs us an extra £200, which we pass onto the customer as part of the all-in price. If our customer wants a cheaper job, they can always find a gas installer who climbs roofs.

We do chimney liners ourselves but only with scaffolding or a 7.5t access platform.

You pays your money, takes your choice, I'm afraid.

 

[andytheplumber]

Water will not come through with a leaded slate they lap under the upper tiles and overlap the bottom tiles, this actes like a slate so it should not leak, as far as insects getting in theres probably thousand of tiny gaps in the roof for them to come in any way. If you look in the loft in daytime with the light out your see loads of light spots.

 

[sambotc]

Depends what he would class a 'rough' hole. Generally we do what you have described though.

Infact I've fitted dozens of vertical flue's in this way over the past few years and only once had a problem which was completly unrelated to your query.

At the end of the day you need to have a hole through the felt regardless and its extremely unlikely you will get a prefect cut around the flue. Then you would have to seal it up etc and like what has been said, your roof is far from sealed from the 'elements' anyway, it's just waterproof.

Also i agree the vaillant weathering slate is naff, better off getting an MTS adjustable pitch lead slate.

HTH Sam

 

[muggles]

I'd agree with that - you're never going to get a perfect hole in the felt and as long as the slate's fitted correctly it won't leak.

Those adjustable slates are crap, part of the reason why I make my own fixed-pitch ones out of lead, to fit the roof I'm working on. That's just me though, it's an unfortunate fact that many plumbers are forgetting their roots and the skill of leadworking is being lost.