Hello everyone, I am planning to install a new facade next year (ventilated facade with wood fiber and fiber cement) on a single-family house built in 1970. Everything is already organized and planned.
In the course of planning the facade (scaffolding setup), I thought about installing the photovoltaic system on the roof. There are several options, and the roofer says the tiles are probably still okay:
1. Photovoltaics on the 50-year-old tiles.
2. Re-roofing with new ventilation, no insulation – additional cost around $30,000.
3. Complete roof renovation including insulation.
Option 1 would just fit the budget, while I would have to wait a few years and rebuild the scaffolding for options 2 or 3.
I am a bit concerned about thermal bridges. The attic floor is unoccupied; the ceiling (ground floor roof) has additional insulation: 16 cm (6 inches) concrete, 2 layers of EPS, screed, and retrofitted with 12 cm (5 inches) Gutex wood fiber insulation and OSB boards for walking on. I have now measured the temperature; it is around 3°C (37°F) with 70% humidity. The joints between the OSB boards all look good.
An energy consultant warns about potential thermal bridges later at the facade-to-roof connection if the roof/exterior envelope is not insulated continuously.
So the question is – install photovoltaics on the roof now, or wait, save up, renovate first and then install photovoltaics?
In the course of planning the facade (scaffolding setup), I thought about installing the photovoltaic system on the roof. There are several options, and the roofer says the tiles are probably still okay:
1. Photovoltaics on the 50-year-old tiles.
2. Re-roofing with new ventilation, no insulation – additional cost around $30,000.
3. Complete roof renovation including insulation.
Option 1 would just fit the budget, while I would have to wait a few years and rebuild the scaffolding for options 2 or 3.
I am a bit concerned about thermal bridges. The attic floor is unoccupied; the ceiling (ground floor roof) has additional insulation: 16 cm (6 inches) concrete, 2 layers of EPS, screed, and retrofitted with 12 cm (5 inches) Gutex wood fiber insulation and OSB boards for walking on. I have now measured the temperature; it is around 3°C (37°F) with 70% humidity. The joints between the OSB boards all look good.
An energy consultant warns about potential thermal bridges later at the facade-to-roof connection if the roof/exterior envelope is not insulated continuously.
So the question is – install photovoltaics on the roof now, or wait, save up, renovate first and then install photovoltaics?
W
WilderSueden21 Dec 2022 09:1150 years is not old for clay roof tiles. If the roof frame is still in good condition and the battens are fine as well, I wouldn’t change anything.