Ventilate internal downstairs toilet.

[nilsac]

Hi all, I’ve got a downstairs WC attached to my utility room.

We’ve had an extension built at the back of it and therefore it no longer has any external walls.

It looks like we’re starting to get damp patches on one internal wall. Which I presume is due to there being no ventilation.

I leave the door open (when not in use) but my question is what is the best way to ventilate this room?

Would simply applying a vent from the WC into the utility room solve this or do I need to put an extractor fan and vent it to an external wall (through the utility room)?

 

[dilalio]

I would investigate other sources for the damp as cloakrooms do not usually create condensation... only incoming cold main will generate this on exposed pipes and plastic cisterns. Unless you have a shower or bath in there!

Extractors in cloakrooms are for getting rid of odours mainly.

Is the wc painted or tiled? Are you getting mould? If there is staining, can you wipe it away or is it ‘in’ the paint/plaster? Former indicative of condensation, latter is rising or penetrating damp.

Check the utility room for sources of damp heat... tumble dryer, ironing, hanging wet laundry... it may be that room that needs the extractor!

Keep us posted.

 

[JohnD]

Condensation is water. There might be a leak.

Of course you need ventilation anyway.

 

[Hugh Jaleak]

I believe it is against Building Regs to have a WC compartment without some form of fixed ventilation if there isn't an openable window in the room. Still need to trace the source of the damp though, what's on the other side of the wall, what type of wall and its history? (Was it previously external, any sign of a DPC etc.)

 

[nilsac]

Thanks for taking the time to reply, the room is painted and we’ve developed small black spots to one of the internal walls about waist high. I have the mains water supply on the other side of the wall with a inspection hatch. The walls solid brick and I’ve looked and there’s no signs of damp on the wall from this side.

I thought it would need some sort of ventilation, so will probably run conduit through stud wall into utility room. Is this enough or does it need to be vented to outside?

 

[Hot&Cold]

Is this enough or does it need to be vented to outside?

Best to extract wc to outside .
Is the utility room ventilated to outside ?

Mechanical extract fans
Any new kitchen or toilet with no openable window; or a bath/shower room or utility room should be provided with a mechanical extract fan to reduce condensation and remove smells. The necessary performance of these extract fans is normally measured in litres per second (l/s) as follows:

• Kitchen - 30l/s if placed over the hob and 60l/s if place elsewhere
• Bath/shower - 15l/s with an additional 15 minute overrun (after the light is switched out)
• Toilet - 6l/s with overrun
• Utility room - 30l/s

info from planning portal uk,hope its up to date .

 

[Hugh Jaleak]

Possibly just condensation then hopefully, get some proper ventilation fitted, and see if it clears.