Vented or unvented soffits

uchuff · 19 Jul 2017 at 11:18

Hi all.

Our 1960s terraced house still has the original soffits, fascias and guttering. I was going to paint the fascias and try to fix the gutter joints but figured it was time for replacement.

We've had three companies round to quote. My preference was the first guy, local sole trader type. He advised no need for vented as the old ones weren't (technically true, although over the years they look to have developed a bit of their own ventilation as there's gaps between them now). The last company recommended vented outright.

I've Googled a bit but it seems inconclusive without potentially other criteria, and none of the companies went up in the attic or on the roof.

Cost difference is negligible so not a consideration.

A couple of the houses on our street that have had theirs done have vents, my parents have a similar house and didn't get vented.

I was wondering if any experts at OCUk could chime in. Any downsides to vented? Any input much appreciated.

fastwunz · 19 Jul 2017 at 16:48

well the whole point of vented sofits is to ensure a continuous flow of air within the roof void in order to avoid a build up of condensation and the impact that can have with dry rot etc on the timber work of the roof structure.

As such, i would always ventilate a roof space

panthro · 19 Jul 2017 at 17:11

If the cost is negligible then surely that's a compelling reason to go vented? As above, it aids air circulation in the roof space and given its an older house it makes sense to go vented.

rexehuk · 19 Jul 2017 at 17:19

I decided to go vented with our recent replacement. Opted for two 150mm holes for vents rather than vents all the way along.

Same situation as you I guess, 1970s with original soffits totally rotted.

Where you based? Can recommend chaps I used as they did a good job.

thezappa · 19 Jul 2017 at 17:45

If you went with unvented you could replace a tile (or two) each side with a vented tile.
I don't think there is any reason not to go with either nowadays since plenty of houses are built unvented, but different era and building practices and all that.

uchuff · 19 Jul 2017 at 18:24

Thanks all.

rexehuk said:
Where you based? Can recommend chaps I used as they did a good job.

West Sussex, near Gatwick.

rexehuk · 19 Jul 2017 at 21:40

uchuff said:
Thanks all.

West Sussex, near Gatwick.

Ahh ok, my chaps only do somerset.

If it helps I paid £500 for 5.2m of soffits/facia full replacement including fully removing old ones (I'm 99% sure it was white asbestos concrete board for the soffit and they didn't care). I had a quote for £300 and did the maths and felt £500 was a more realistic price (and the £300 guy promised twice and failed to call - phoned on day I was having new ones installed!)

After some thought, quite sure my soffit vents are 70mm, not 150mm as that is huge!

uchuff · 20 Jul 2017 at 00:00

Front and back, remove and replace soffits, fascia, gutter - standard three bed terraced house, three quotes so far:

£900
£1600+£700 Asbestos removal if needed (likely to be I would guess)
£3k

Middle quote I think bumped at least a little by full scaffolding front and back plus bigger company with premises versus first quote working off ladders, although first quote still seemed a bit cheap. Last lot spent 2 minutes and took a couple of photos, no measurements, hardly any detail on quote.

robj20 · 20 Jul 2017 at 07:18

You only go unvented when you use a breathable membrane under the tiles/slates. If your not changing that you should maintain the ventilation at the soffits.

the_r_sole · 20 Jul 2017 at 08:12

On a retrofit I would always go vented.
With unvented it might be ok, but has the potential to throw up a problem. With vented the wise case scenario is slightly too much ventilation which is no problem at all

rexehuk · 20 Jul 2017 at 16:19

900 quote seems fair for off ladder work mine was full gutter replacement too.

Chuck a thing up on mybuilder If you didn't already? There's a soffits category.

Mysterae_ · 23 Jun 2022 at 14:02

Thread bump.

I started by writing do I need soffit vents as I've just had new soffits and facias fitted and they didn't fit any soffit vents. Then going over the invoice before paying it says that they should be fitted and I'm paying for them so that answers that.

I'm just wondering how many vents should be fitted on a 13m length, or loft floor surface area of 143m2? Specifications on different websites vary.

Why are trades such a pain to deal with.

Simon42 · 23 Jun 2022 at 14:22

Mysterae_ said:
Thread bump.

I started by writing do I need soffit vents as I've just had new soffits and facias fitted and they didn't fit any soffit vents. Then going over the invoice before paying it says that they should be fitted and I'm paying for them so that answers that.

Did they fit vented fascia board instead which would have vents behind the guttering?

These days the options are vented fascia boards, vented soffit board or the 70mm round vents fitted to the soffit after.

Mysterae_ · 23 Jun 2022 at 23:19

As far as I can tell there's no vents at all. The facia boards go up to the roof tiles and the soffits underneath have none either. The roof has zero ventilation apart from maybe between the wooden roof rafters(?) and the tiles.

happy_2008 · 24 Jun 2022 at 09:00

Definately vented here, it the winter months my loft was dripping with condensation despite having vented soffits. Had to fit additional spacers to clear the problem up and increase air flow.