Edwardian roof ventilation

[cookerooby]

Am in process of selling an Edwardian two bedroom terrace. Prospective buyers survey has pointed out that roof void has no air vents. Due to time of construction I am presuming that air vents may not have been part of building specification. I am wondering whether original constructors would have incorporated some other ventilation method and what I need to look for to confirm its existence. Also survey stated that there were an inadequate number of air bricks to provide ventilation under floorboards of which the lounge floorboards are exposed and the rest are under some laminate (apologies to those offended it was not my doing!) Are there any tell tale signs of damage due to this supposed defect? Hope someone can help.

 

[Gervase]

Edwardian houses didn't have air vents. Air circulates freely around the roof space because the Edwardians didn't use modern non-breathable membranes under the slates.
As for the underfloor vents, the only sure-fire way to see if there's any damage is to look under the floor. You could try jumping up and down in various parts of the room to see if any areas have a more noticeable 'give', indicating maybe some decay, but it's a hit and miss process.
Are there any vents which may have been covered with soil or pathways added later? Uncover those and you should have no worries from the surveyor.
It sounds like the typical building society survey based on the specifications of a modern (post 1914) house, and which has little relevance to an Edwardian building.

 

[Lime]

Ventilation of the loft/roof space was provided by the gaps under the tiles and the large gaps around the eaves between the external walls and tiles.
If insulation & roof membrane/felt have been fitted the gaps around the eaves need to be free and clear of any insulation.
Generally they are sufficient.
As Gervase makes mention, the comment about lack of ventilation grills may be ignorance on behalf of the surveyor but it could be valid if ventilation has been stopped up and if extra insulation has been installed without due consideration for free air movement.

As for under the floors, I'm of the belief that you can't have too much of it to keep the floors in good condition.
Make sure the vents are clear of external obstructions and also free of blockages caused by spider webs etc.
Also ensure that there is adequate cross-ventilation from one side of the house to the other.

 

[Matt Green]

Also survey stated that there were an inadequate number of air bricks to provide ventilation under floorboards of which the lounge floorboards are exposed and the rest are under some laminate (apologies to those offended it was not my doing!) Are there any tell tale signs of damage due to this supposed defect? Hope someone can help.

Please don't make holes in your walls for more sub-floor air vents, it's a bit counter-productive. As mentioned, the surveyor is trying to apply modern building regs to a period property. Find all the vents you have and make every effort to make sure they are clear. Make sure all the external ground levels are at least 6" below finished floor height.

If there is sufficient ground water beneath the floor to evaporate into the void, there is a risk of insect attack, particularly at the bearings. The first sign of a floor compressing is that it will drop next to the wall. There might not be any bounce, but the gap between it and the skirtings will gradually increase.

It might be an idea to lift a board or two to find out what the void looks like. If it's blowing a gale through there and the solum is dry, you don't have much to worry about. If it looks like a riverbed and you find frogs, further effort may be required.


Matt