home ventilation advice

the gavel · 26-07-2014 2:33pm #1

Hi.

We recently bought a 1930s terraced poured concrete house .

There was no ventilation in any walls only fireplaces in 2 sitting rooms and 2 bedrooms.

the kitchen , bathroom and box room have nothing .

We stripped the house back to the brick and added 50 insulated plasterboard to all external walls and the whole kitchen as it was an extension .

There was storage heating in the house but now there is gas central heating .

My questions

When it was stripped back there was no signs of damp at all, now I have insulated will I now the damp ?

Will the fireplaces do as ventilation on there own ? and I'm going to change the windows so would trickle vents and the fireplace be enough for those rooms

What would you do in the bathroom, kitchen and box rooms

Should I just pit a vent in all rooms ? I don't want it to cold .

Any advice would be great

Charlie-Bravo · 26-07-2014 2:49pm

Good ventilation helps good comfort. Part F of the Building Regulations deals with ventilation. All habitable rooms should have natural background ventilation - ideally with fixed-open vents, not close-able ones! Trickle vents in new windows will help. To remove moisture created by normal living through cooking, drying clothes, sleeping and doing cartwheels it is critical to have the vents for this purpose.

With regards to burning fossil fuels such as gas, it's important to have fresh air supply, one for creating a draft up the chimney and the other for providing oxygen to the appliance.

For bathrooms and cookerhoods etc, mechanical extraction is important. Having it vented to the outside air.

There are various ways and positions for locating vents, and with a 1930's build, there may be some indirect ventilation with sub-floor voids below the suspended timber ground floor (if that's what you have). The suggestion would be to have a building surveyor review the ventilation as it is and recommend improvements.

the gavel · 26-07-2014 5:34pm

Thanks for getting back to me

i will have a building surveyor have a look, but my experience with them is they will just tell you what the new regs are , and that is not always the best way as most of the regs for everything these days are over the top .

i dont want to go over board and be wasting the heating all winter.

is there any way to test your house for damp and moisture levels ?
and would running a dehumidifier once a day prevent damp?

as for airflow , when we are home we usually have a few windows open in the summer anyway cause the house is so hot from the insulation not sure about the winter as we have only moved in a few months

i was going to put in a extractor fan in bathroom to the outside or( would it be possible to vent to attic? with a filter or somthing)

as for the kitchen the cooker hod is an extrator with charcoal filter (not very good really) but the only location an extractor fan could go is above the window

MicktheMan · 26-07-2014 7:26pm

the gavel wrote: »

1.i dont want to go over board and be wasting the heating all winter.

2. is there any way to test your house for damp and moisture levels ?
3.and would running a dehumidifier once a day prevent damp?

4.as for airflow , when we are home we usually have a few windows open in the summer anyway cause the house is so hot from the insulation not sure about the winter as we have only moved in a few months

5.i was going to put in a extractor fan in bathroom to the outside or( would it be possible to vent to attic? with a filter or somthing)

6.as for the kitchen the cooker hod is an extrator with charcoal filter (not very good really) but the only location an extractor fan could go is above the window

1. an adequately ventilated house will use less energy to be comfortable in winter than either an over- or underventilated house.
2. Yes, during the heating season
3. a dehumidifier is expensive to run and will not give fresh air (i.e. remove pollutants)
4. Insulation works both ways; your house should be cooler in summer if the insulation is working. In winter, opening windows for a couple hours per day is inadequate for proper ventilation, imo. Little and often is a lot better than a large purge. Ventilation is in the b regs to primarily mitigate against high internal moisture levels and damp during the heating season, not during the summer.
5. Extract at source straight to the outside. Do not vent into the attic.
6. see 5.

29-07-2014 10:39am

+1 to MicktheMan

the gavel wrote: »

i was going to put in a extractor fan in bathroom to the outside or( would it be possible to vent to attic? with a filter or somthing)

In my bathroom I installed an extrat fan in the ceiling of the shower cubicle (a 12V unit for safety). In the attic I connected this fan to a flexiable hose and ducted this to a vent in the soffit.

as for the kitchen the cooker hod is an extrator with charcoal filter (not very good really) but the only location an extractor fan could go is above the window

These units are useless, but I think you know that.