Uploaded February 2026 | Updated September 2026, 1 week ago
👇 TuffX Infinity Framed Roof Lights
go.skill-builder.uk/tuffx
_______________________
Fitting a rooflight to a flat roof looks like the easy part of the job, and it is, right up until the upstand is wrong.
Get the kerb right and the rooflight itself is a twenty minute job. Bead of sealant round the top, lower it on, screw it down. Get the kerb wrong and you are stripping felt off in the rain and starting again, which is exactly what happened to us on this one.
In this video we fit a set of Infinity framed rooflights from TuffX onto timber upstands on a low pitched flat roof. We cover the kerb height and pitch these units need, both approved fixing methods, the sealant detail, why we ended up swapping felt for lead on the upstand, and what the glazing gives you once it is in.
Infinity rooflights are fixed units designed for flat and very low pitch roofs, manufactured in the UK and supplied complete and ready to go on. Standard double glazed units give a centre pane U-value of 1.2 W/m²K, with triple glazed available down to 0.7 W/m²K. Frames are thermally broken aluminium, supplied as standard in anthracite grey or black, with other RAL colours available.
If you are planning a flat roof extension or a garden room, the link above has the full Infinity range.
_______________________
KEY TAKEAWAYS
- The upstand decides everything. Square, fully supported, minimum 150mm high, and pitched at a minimum of 5 degrees so water runs off the glass instead of sitting on it and collecting dirt.
- Size the upstand for the finished covering, not the bare timber. Ours came up fractionally small once it was felted and the units sat proud. Stripping the felt back 80mm from the top and running lead around instead gave a thinner build-up and let them seat properly.
- Two approved fixing methods. External fixing gets you watertight fast from above. Internal fixing with straps is the answer where external access is tight or you want the waterproofing left undisturbed.
- Fixings are stainless steel, 60mm long, set in around 100mm and spaced at regular intervals, finished with anthracite caps to match the frame. Use packers so you do not distort the frame as you pull it down.
- Sealant is a continuous bead on top of the upstand, applied before the unit goes on. If you are reaching for more silicone to close a gap afterwards, the kerb is wrong.
- These units are heavy. We had four people on the large ones and two on the small one. Plan the lift before the sealant goes down, because once it is piped you are committed.
- Performance is designed in rather than corrected on-site. Thermally broken frame, 1.2 W/m²K as standard, 0.7 W/m²K triple glazed, with sound reduction and solar control coatings available.
- Standard sizes are stocked with typical lead times of three to four working days, bespoke sizes are available, and every unit carries a ten-year guarantee.
_______________________
WATCH NEXT
youtu.be/i41oW85zPm8
youtu.be/T_mOHvaSKJU
_______________________
CHAPTERS
00:00 Dropping the rooflights on
00:25 Two approved fixing methods
00:35 External fixing and the 5 degree kerb pitch
01:00 Fixing through the frame
01:17 Internal fixing with straps
01:33 Why we stripped the felt and used lead
02:10 Getting the upstands square
02:33 Stainless fixings and caps
02:52 How many people you need to lift one
03:10 U-values and glazing options
03:40 The finished result
03:52 UK manufacture, lead times and guarantee
04:21 More from Skill Builder
_______________________
Building a flat roof extension this year? Tell us what your kerb detail looks like in the comments and we will have a look.
_______________________
TuffX Social links
facebook.com/TuffxGlass
instagram.com/tuffxglass
https://x.com/tuffx_glass
linkedin.com/company/tuffx-glass
#rooflights #flatroof #extension #skillbuilder
==================================
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👇 TuffX Infinity Framed Roof Lights
go.skill-builder.uk/tuffx
_______________________
Fitting a rooflight to a flat roof looks like the easy part of the job, and it is, right up until the upstand is wrong.
Get the kerb right and the rooflight itself is a twenty minute job. Bead of sealant round the top, lower it on, screw it down. Get the kerb wrong and you are stripping felt off in the rain and starting again, which is exactly what happened to us on this one.
In this video we fit a set of Infinity framed rooflights from TuffX onto timber upstands on a low pitched flat roof. We cover the kerb height and pitch these units need, both approved fixing methods, the sealant detail, why we ended up swapping felt for lead on the upstand, and what the glazing gives you once it is in.
Infinity rooflights are fixed units designed for flat and very low pitch roofs, manufactured in the UK and supplied complete and ready to go on. Standard double glazed units give a centre pane U-value of 1.2 W/m²K, with triple glazed available down to 0.7 W/m²K. Frames are thermally broken aluminium, supplied as standard in anthracite grey or black, with other RAL colours available.
If you are planning a flat roof extension or a garden room, the link above has the full Infinity range.
_______________________
KEY TAKEAWAYS
- The upstand decides everything. Square, fully supported, minimum 150mm high, and pitched at a minimum of 5 degrees so water runs off the glass instead of sitting on it and collecting dirt.
- Size the upstand for the finished covering, not the bare timber. Ours came up fractionally small once it was felted and the units sat proud. Stripping the felt back 80mm from the top and running lead around instead gave a thinner build-up and let them seat properly.
- Two approved fixing methods. External fixing gets you watertight fast from above. Internal fixing with straps is the answer where external access is tight or you want the waterproofing left undisturbed.
- Fixings are stainless steel, 60mm long, set in around 100mm and spaced at regular intervals, finished with anthracite caps to match the frame. Use packers so you do not distort the frame as you pull it down.
- Sealant is a continuous bead on top of the upstand, applied before the unit goes on. If you are reaching for more silicone to close a gap afterwards, the kerb is wrong.
- These units are heavy. We had four people on the large ones and two on the small one. Plan the lift before the sealant goes down, because once it is piped you are committed.
- Performance is designed in rather than corrected on-site. Thermally broken frame, 1.2 W/m²K as standard, 0.7 W/m²K triple glazed, with sound reduction and solar control coatings available.
- Standard sizes are stocked with typical lead times of three to four working days, bespoke sizes are available, and every unit carries a ten-year guarantee.
_______________________
WATCH NEXT
youtu.be/i41oW85zPm8
youtu.be/T_mOHvaSKJU
_______________________
CHAPTERS
00:00 Dropping the rooflights on
00:25 Two approved fixing methods
00:35 External fixing and the 5 degree kerb pitch
01:00 Fixing through the frame
01:17 Internal fixing with straps
01:33 Why we stripped the felt and used lead
02:10 Getting the upstands square
02:33 Stainless fixings and caps
02:52 How many people you need to lift one
03:10 U-values and glazing options
03:40 The finished result
03:52 UK manufacture, lead times and guarantee
04:21 More from Skill Builder
_______________________
Building a flat roof extension this year? Tell us what your kerb detail looks like in the comments and we will have a look.
_______________________
TuffX Social links
facebook.com/TuffxGlass
instagram.com/tuffxglass
https://x.com/tuffx_glass
linkedin.com/company/tuffx-glass
#rooflights #flatroof #extension #skillbuilder
==================================
👇 SUPPORT SB - BECOME A MEMBER
youtube.com/channel/UC9GdB6vG6m6cDAwrTAWXgyg/join
📪 JOIN OUR NEWSLETTER
skill-builder.uk/signup
🛒 SEE OUR FAVOURITES ON AMAZON
amazon.co.uk/shop/skillbuilder
🎧 LISTEN TO OUR PODCAST
blubrry.com/skillbuilder/subscribe
🎬 OUR VIDEO LIBRARY
youtube.com/@SkillBuilder/videos
🔗 SEE EVERYTHING SB ON LINKTREE
https://linktr.ee/skillbuilder
facebook.com/skillbuilderchannel
tiktok.com/@skillbuilder
instagram.com/skill_builder
(As an Amazon Associate, we earn from qualifying purchases)
==================================
OUR FAVOURITE CHARITIES
👷 BAND OF BUILDERS
bandofbuilders.org
⛯ THE LIGHTHOUSE CHARITY
lighthousecharity.org
💧 CHARITY WATER
charitywater.org
