1910s semi detached house with original roof. L shaped floorplan with room in roof above the bulk of the house (original rather than conversion), the eaves at front are inaccessible, the eaves at back have insulation in the joists below with planks ontop to form a storage space + plastic sheet pinned to under the rafters to deflect dust, and the offshoot out back above the bathroom is bare plaster and lath under foot.
Poking around the loft with 3 objectives
a) making the entire house more thermally efficient
b) expanding the climate controlled space into the eaves and back loft
c) ensuring longevity of the house structure
Current things of note:
The house has no soffit or fascia board to speak of so no ventilation coming from there.
I need to buy an endoscope or something to confirm but I think the wall cavity is open topped and vents into the eaves. This might be the original source of ventilation instead of soffits. Said cavity has since been filled with insulation, which then failed because of bad gutters soaking it. So what if any ventilation is left or ever was is unknown.
Supporting that theory the offshoot has two ventilation bricks right below the eaves (one bunged up). The gable wall has two airbricks just below attic joist height and one mid way up the attic wall. The front though has one airbrick below attic joist level.
No sign of roof or ridge ventilation though. The neighbouring set of semis of similar vintage but slightly different design have had 6 roof vents per house retrofitted. Maybe the gaps in the slate count as sufficient.
The off shoot kind of has joist level insulation. Looks like someone carried the insulation up to the loft then just threw it on the floor. Some spots have 2ft tall, some none. No idea what happened there. No sign of work that would have meant taking it up.
There's a terribly installed bathroom ventilation fan ducted to the top roof. They tried their best to make a celtic knot out of the flexible duct. Not surprised if it leaks wet air so that's getting taken out.
At a current balmy 7c weather forecast and the internal heating off there is condensation on the underside of the slates. A few weeks ago when it was colder and the heating was on the roof was completely sopping. I could squeeze water out the battens by poking them. Maybe someone had just had a shower as well. Doesn't help that theres two spots of daylight coming through.
The current insulation between the attic room and roof is just bunged in the entire void. No sign of a membrane, no sign of a gap above or below the insulation. This goes more or less against everything I know about rafter insulation. Theres no sign of damp inside the room but that doesn't mean the rafters inside haven't turned to mush without anyone seeing.
Potential action
I'm getting roofers to repair some slate and redo the ridgeline + someone to replace the gutters. While they are up there should I get some form of ventilation retrofitted? It weirds me out that there isn't any, but it also feels weird to add some when there was none originally. The cavity is a wildcard since the failed insulation is to get sucked out.
Does the existing attic insulation need ripping out? I'd like to think whoever put it in knew what they were doing. The original roof implies it didn't get installed from above and and the fact an original gas lamp is in the room implies it didn't come from below. But then 1910 seems early for people to be adding insulation so maybe someone took the time to plumb the gas lamp back in.
I'd love to install insulation between and under the rafters. Extra useable space. The current eaves access door isn't anything like air tight so heats leaking that way. Taking the insulation from the joists would make for easier rewiring of the house. Barrier between the rafters and wet internal air (though joist insulation would also achieve this). But then the lack of any membrane or felt makes things non standard. To ensure enough ventilation I'm thinking of attaching insulation only under the rafters so they can breath as much as possible. Would this all go very badly?
Hovering over all this is a big button that says get the roof replaced. It would certainly be simpler but no one wants to spend thousands and thousands without checking the alternatives first.
Poking around the loft with 3 objectives
a) making the entire house more thermally efficient
b) expanding the climate controlled space into the eaves and back loft
c) ensuring longevity of the house structure
Current things of note:
The house has no soffit or fascia board to speak of so no ventilation coming from there.
I need to buy an endoscope or something to confirm but I think the wall cavity is open topped and vents into the eaves. This might be the original source of ventilation instead of soffits. Said cavity has since been filled with insulation, which then failed because of bad gutters soaking it. So what if any ventilation is left or ever was is unknown.
Supporting that theory the offshoot has two ventilation bricks right below the eaves (one bunged up). The gable wall has two airbricks just below attic joist height and one mid way up the attic wall. The front though has one airbrick below attic joist level.
No sign of roof or ridge ventilation though. The neighbouring set of semis of similar vintage but slightly different design have had 6 roof vents per house retrofitted. Maybe the gaps in the slate count as sufficient.
The off shoot kind of has joist level insulation. Looks like someone carried the insulation up to the loft then just threw it on the floor. Some spots have 2ft tall, some none. No idea what happened there. No sign of work that would have meant taking it up.
There's a terribly installed bathroom ventilation fan ducted to the top roof. They tried their best to make a celtic knot out of the flexible duct. Not surprised if it leaks wet air so that's getting taken out.
At a current balmy 7c weather forecast and the internal heating off there is condensation on the underside of the slates. A few weeks ago when it was colder and the heating was on the roof was completely sopping. I could squeeze water out the battens by poking them. Maybe someone had just had a shower as well. Doesn't help that theres two spots of daylight coming through.
The current insulation between the attic room and roof is just bunged in the entire void. No sign of a membrane, no sign of a gap above or below the insulation. This goes more or less against everything I know about rafter insulation. Theres no sign of damp inside the room but that doesn't mean the rafters inside haven't turned to mush without anyone seeing.
Potential action
I'm getting roofers to repair some slate and redo the ridgeline + someone to replace the gutters. While they are up there should I get some form of ventilation retrofitted? It weirds me out that there isn't any, but it also feels weird to add some when there was none originally. The cavity is a wildcard since the failed insulation is to get sucked out.
Does the existing attic insulation need ripping out? I'd like to think whoever put it in knew what they were doing. The original roof implies it didn't get installed from above and and the fact an original gas lamp is in the room implies it didn't come from below. But then 1910 seems early for people to be adding insulation so maybe someone took the time to plumb the gas lamp back in.
I'd love to install insulation between and under the rafters. Extra useable space. The current eaves access door isn't anything like air tight so heats leaking that way. Taking the insulation from the joists would make for easier rewiring of the house. Barrier between the rafters and wet internal air (though joist insulation would also achieve this). But then the lack of any membrane or felt makes things non standard. To ensure enough ventilation I'm thinking of attaching insulation only under the rafters so they can breath as much as possible. Would this all go very badly?
Hovering over all this is a big button that says get the roof replaced. It would certainly be simpler but no one wants to spend thousands and thousands without checking the alternatives first.
