Ventilation for kitchen extension

[Triggaaar]

We've just started our kitchen extension (foundations completed, brick and block about to start).

 

The finished room will 7.5m wide x 9.6m long, 2.7m high (internal). The east elevation will be mostly glass sliding doors. to the garden.

The north and south elevations will be brick & block with full fill cavity.

The west then joins the rest of the old Edwardian house.

There will be underfloor heating on top of PIR insulation on top of the concrete oversite.

We'll have a new warm flat roof, with 1 largish rooflight, with solar restricting glass.

The will be a new log burner, which might only be 5kw.

 

We currently have no ventilation plan at all (other than an extractor fan in the kitchen, which will exhaust straight out the wall).

The glass doors will not have trickle vents.

 

What would you guys suggest as possible solutions?

 

Many thanks

Edited November 26, 2019 by Triggaaar

[ToughButterCup]

As Sensus suggests, you might like to think about the log burner. 

You might be able to put one in a closed loop ventilation system, perhaps? 

[ProDave]

9 hours ago, Sensus said:

 

Discuss this with your Architect or BCO.

 

You are only allowed solid fuel appliances in a room with an extract fan if they have a direct external air supply (ie. they are effectively 'room sealed') and if spillage tests have been performed (theory being that even with a room-sealed appliance, you can leave the door open with smouldering logs in it, and CO can be drawn into the room).

 

 

BC have not mentioned that here. They passed our plans with a stove without comment.

 

Our stove is room sealed.  The room (kitchen / diner aka family room) has both mvhr in and out (one at each end) and having just balanced it recently I made sure the inlet and outlet flow rates in that room are the same so there is no net flow into or out of that room.

 

If you open the stove when burning no smoke appears to spill out, so I guess that is a pass for the spillage test then.

[Triggaaar]

Thank you all for the replies. I have no idea what the solution is.

[ToughButterCup]

You have no idea how serious the issue is_ yet. You could try asking your BCO. But I'd be wary of doing that straight off ; test the water first. 

[Triggaaar]

On 27/11/2019 at 07:58, Sensus said:

 

Discuss this with your Architect or BCO.

 

You are only allowed solid fuel appliances in a room with an extract fan if they have a direct external air supply (ie. they are effectively 'room sealed')

 

Thank you. We'll have a direct external air supply straight into the burner. BCO is happy so far, but then he's not the one fitting it.

 

 

 and if spillage tests have been performed (theory being that even with a room-sealed appliance, you can leave the door open with smouldering logs in it, and CO can be drawn into the room).

 

Mmm. We're presumably not the first people to have a log burner in an open plan kitchen - how do people usually get around this issue?

 

Thanks

 

[Triggaaar]

On 27/11/2019 at 17:49, Sensus said:

The spillage test is described here. The problem - as with noise testing and air testing - is what to do if you fail, since the chances are you'll already be using the minimum acceptable fan...

 

What if you change the extractor to re-circulate the air, instead of extract it?

[ProDave]

15 minutes ago, Triggaaar said:

 

What if you change the extractor to re-circulate the air, instead of extract it?

Building regs demand you have a certain extract rate from a kitchen unless you have MVHR.  In our case the mvhr inlet at one end and extract at the other are now ballanced so there should be no net flow of air into or out of the room, and hence no pressure change.

[Triggaaar]

Just now, ProDave said:

Building regs demand you have a certain extract rate from a kitchen unless you have MVHR.

 

Although I know close to nothing about MVHR, I was thinking of having it. We have no trickle vents for the room, so I thought about a single room solution. I'd also consider a solution for the whole house, but I've had a brief look at other threads, which mainly highlight just how little I know about it all. I mentioned MVHR as a solution to the BCO and he started asking me questions I don't yet know.

 

In our case the mvhr inlet at one end and extract at the other are now ballanced so there should be no net flow of air into or out of the room, and hence no pressure change.

 

Does a single room MVHR usually have separate inlets and extracts, or are they sometimes together? Is the MVHR constantly on, or does it switch on when it detects the need, or what?

 

Thanks

[ProDave]

I have never looked at single room mvhr, perhaps others can comment.

 

If you are not having mvhr then it won't pass building regs without an extract fan AND trickle vents to let air back in.

[Triggaaar]

Bump.

 

I'd like to have a single room MVHR solution and I'll soon be doing the wiring, so need to decide where the inlet and extract for the MVHR go. Recommendations for the make and model of MVHR would also be much appreciated.

 

Thanks

 

 

[matt_bag]

Hi,

 

You need a fan that does 60l/s in a kitchen to meet building regs. The Vent Axia HR200V heat recovery system does 70l/s and may be the best option here!