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I've been looking into the methods (and depth of) assessment prescribed for the suitability of a house for Green Deal interventions - specifically insulation upgrades.
I know we have discussed such scenarios in great depth here but it occurred to me that we don't have a resource of anecdotal evidence of issues, defects, and problems before or after such interventions. Pictures would be a great way to illustrate such issues
In other words, defects which would initially be hidden beneath fabric and therefore *invisible?* to the skilled surveyor without intrusive tests. I.E. drilling holes or hacking off render for example. The example I've given is for walls but i'm also interested in roofs and floors and the interaction and interfaces between them.
I don't mean this thread to be negative to the green deal but I think it is very important that people who may take this up are aware or potential pitfalls
So does anyone have any pictures? I'll load some up later
Ok, here's a start. A concealed timber lintol in the outer *leaf* of a 9 inch solid brick wall. At some time in the past the original window had been removed and bricked up
And here's one on a different elevation where the window remains. The render was adhered to metalic lath nailed to the timber. No visible sigh therefore that the lintol was timber
So what would be the effect of internally or externally insulating such walls with hidden lintols such as these under a Green Deal proposal?
Would they even be picked up in a Green Deal Assessment procedure given that they are in areas of masonry where they really shouldn't be? Ie, at the outer facing edge of a solid brick wall.
The circumstances being that the cavity wall adjacent to the flue void had been retro - insulated.
There were lots of voids where the insulation had not been installed completely. Also there is a question about whether the wall itself was suitable for cavity wall insulation given its severe exposure.
I believe the badly installed insulation promoted conditions within the voids and flue promoting the dry rot outbreak
This is what happens when a recessed downlight is fitted into a top floor ceiling - draughts! Not really a hidden problem, just not thought through by homeowner and installer.
It's a Flir i7, we paid just under £2K for it including VAT. The cheapest model in the range is the i3 at circa £850 + VAT, which looks identical but has a quarter of the field of view.
Very easy to use but needs care in the settings and interpretation to get the best out of it.
Not strictly a hidden defect, but present in a large number of houses.
This is an internal block wall with a radiator BEHIND it. The other side of the wall is at 18 degC. If you have radiators on external walls (a hidden defect?) always make sure you have insulated radiator foil behind.
If your radiators are on outside solid walls or you have no cavity wall insulation, either get the walls insulated or move the radiators. Seriously.
Never taken one from the loft but here is one taken of the floor in an (unheated) room above a ceiling with downlights. You can not only make out the position of the downlighters but you can see the how the heat has filled the void between the floor joists.
Also watch out for thermostats. These examples are both positioned on a dry-lined external wall.
The first one actually has a room temperature of 25.4 deg C but draughts into the drylining results in a perceived temperature of 22 deg C, result = excess heat loss and overheating.
In the second example the drylining is OK but the draught is coming in via the electrical conduit and blows out the side vents. Again, excess heat loss and overheating as the stat is perceiving a lower temperature.
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