Help :-( urgent Structural Warranty and compromised air vents issue

[DeanAlan]

BC have signed off.

 

We have 5 air vents on either side of large extension but due to the walls being SIPs then periscope vents could not be used (no cavity for them to rise in). We used straight through vents (in agreement with architect and building control).

 

10 vents have 150mm clearance but 2 of them - due to proximity to neighbours foundation and wall (600mm away) are at ground level. I might be able to dig down a little but not sure I can get 150mm clearance that warranty people seem to required (BC 75mm I believe).

 

So, I am considering installing a periscope outside and building some brickwork or forming concrete around it for mechanical stability. Periscope would need a waterproof connection to the air-vent that is there - probably just a good sealant.

 

Any thoughts?

 

Structural Warranty surveyor is driving me mad - but that is another story which may go public if I can't resolve in a constructive fashion.

 

Appreciate any constructive ideas from folks here. Really thought I had put this issue to bed but ....

[Conor]

What's below the vent at ground level? Paving, grass? You could just locally lower the ground level as you suggest, backfill with pebbles up to 150mm to reduce splashing. What's stopping you from doing this? It would only need to be 200mm or so wider than either side of the vent. Drainage needed tho or it'll fill with water to ground level during heavy rain. Photos?

Edited January 17, 2023 by Conor

[DeanAlan]

Yes, I did consider that but 1) struggling to get requirement out of the warranty folks 2) NHBC say that if you do that you need 600mm around the vent at that lower level and our neighbours foundation is at that level at about 400mm out.

 

I may try the excavation route - as much as I can - and see what they say but need a backup plan and was thinking about building a periscope up.

 

cheers,

=- Dean

[Hilldes]

@DeanAlan I replied on my thread that you linked with one suggestion of how to seal and cover the pericope vents.

 

On 17/01/2023 at 13:07, DeanAlan said:

 

Structural Warranty surveyor is driving me mad - but that is another story which may go public if I can't resolve in a constructive fashion.

 

Mine too. Over 3 months since I got building control final certificate and still we splitting hairs. Separate thread on some of the challenges I have faced linked. What I found was building control have done their job highly effectively and been pragmatic but the warranty provider's technical auditors are a law unto themselves. It has cost me thousands.

 

 

 

[DeanAlan]

Ouch, that is very worrying @Hilldeswe should get BC completion next week and need SW cert asap to unlock a remortgage.
For the moment I will not say who the warranty provider is.

 

I've sent them a proposed design for external periscope on the 2 vents in defect due to limited clearing to get their written approval prior to doing the work. At the moment silence and if I do the work ahead of their agreement I fear (might happen anyway) and continual "no" without an answer or advice on a resolution.

 

I'll read your thread - hope you come through it.