Soffits and ventilation holes

[mikeF00]

Hi, I’ve got a fairly unusually designed house in that we’ve got a smaller lower roof section with soffits above the ground floor( see pictures) The house is cold all the time ( especially the hall way) and I’m convinced it’s due to the shear number of ventilation holes we have in lower soffit and the cold air seeping into the house between the lower floor ceiling area and upper floor. As anybody else got any Opinion about this?.if I’m right ,what can be done? I realise there might ventilation issues but other houses without this lower roof ( and ventilation holes ) don’t have ventilation issues ?
Any comments greatly appreciated

 

[KenGMac]

mikeF00, good evening.

Just a consideration But?

Is there a possibility that the garage roof is not Insulated? The developer MAY??? have taken the view that because the garage is not a "living space" and there is not living space above [at least] part of the garage why should they spend money insulating the roof?

There is of course the other option? that there is no insulation in the loft area on the projection?

Any access to this area? I doubt it? If not how about some investigations? using a very, very thin screwdriver push a hole into the ceiling to see if you can "feel" glass wool insulation?

Ken.

 

[mikeF00]

Hi thanks for replying. The soffits are no where near the loft. The ventilation vents on to the joist space between floors(ground and first floor). Mainly above my hall ceiling.
As most houses don’t have specific ventilation for his area , I’m wondering why mine does ?

 

[KenGMac]

mikeF00, good evening, again.

I do not mean the main roof, I was referring to the images you posted, those appear to be the ground floor "out shot" that protrudes forward of the main houses front elevation, and contains the front entrance door and the garage door.

It will be a fairly small area probably less than 2.5.m to 3.0.m protrusion from the main elevation??

Ken

 

[mikeF00]

Hi again. I insulated the garage roof, back of the garage door and mating garage walls last year. The result is that the garage itself is now quite warm( well..never freezing). But due to the cold air pouring into the cavity space between floors , the hallway , kitchen are always quite cold. Do the joists have to be specifically ventilated between ground and first floor ? I mean ...is yours ?

 

[KenGMac]

I mean ...is yours ?

No? I live in a Georgian property, so no such issues

But due to the cold air pouring into the cavity space between floors

How is the air getting in there? The convention is that that type of space, does not need to be vented?

Ken.

 

[mikeF00]

The air is getting in through the vent holes show in the pictures. well, I assume it is.

 

[mikeF00]

...I could do with getting an endoscope and having a nosey.

 

[KenGMac]

Right.

It is a necessity to vent such spaces to stop condensation build up.

What happens is that the temperature above the insulation is cold, little of the heat in the house can get up there because of the Insulation.

BUT ? water vapour can / will / does permeate the plasterboard + the Insulation, once the water vapour hits the "cold" air in a roof void [or similar] it will begin to condense, this condensing water can and does cause all sorts of problems, wood rot being one of them.

To stop the above condensation ventilation is a MUST to ensure any moist [cold] air is not allowed to condense in the roof void.

In really bad conditions I have seen droplets of condensed water dripping from rafters on to the insulation and then on to the upper surfaces of the plasterboard, all hell breaks loose if there is, as I have seen a steel framed truss system roof, with minimal / no eaves venting.

OK the Idea of ventilation of a roof seems perverse but it is a real necessity

What i am having trouble with is to understand how air is getting in between the floors from the out shot roof void?

Ken.

 

[^woody^]

I'd suspect any coldness is due to undersized heating emitters, not a few vents in such a small area of roof.

 

[mikeF00]

You mean ‘radiators’ ? There are about 15 vent holes in the soffits and they didn’t vent the roof space- just the space between the floors.

 

[catlad]

Sounds like they have been installed wrong if your sure that is happening.

 

[datarebal]

They do vent the small roof space.

I don't see how they would vent between the ceiling and the floor above.
What's holding up the outer skin of brickwork that is hidden by the little roof?
Try taping them up and see if it makes a difference.