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Extension roof opening or skylight

Ensuring the structural integrity of your roof when adding skylights or dormers is crucial, as improper support can lead to sagging or further damage. This guide highlights the importance of professional adjustments and regular maintenance to prevent costly repairs, ensuring longevity and functionality for your roof's additions.

For an extension roof with a roof opening (dormer) and/or skylight, or one that was added later, special attention must be paid to the beam structure. To install larger skylights or skylights, load-bearing beams, which are part of the roof structure, must be regularly interrupted. If this is not properly supported, there is a real risk of the roof surface sagging. The adjustments must be carried out professionally and properly .

If the adjustments are not carried out professionally and properly , improvements/modifications to the structure will be necessary. Be aware that the roof surface may sag or weaken further if the structure is not repaired (in time). However, this repair is usually relatively simple; it can be remedied by inserting a few beams between the existing purlins.

Often, due to finishing, it's not visible whether the beam structure around the roof opening has been modified. In that case, there are no visible deviations that would indicate that any modification would be improper.

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Lead connections roof opening

The lead connections around the roof opening (of the extension) should be checked automatically.

  • Check lead connections around roof openings annually. Any blown-up lead can be repaired immediately.
  • Remove dirt and leaves around the roof opening to prevent obstructions in the drainage system.

If, after inspection, the lead connections around the roof openings (of the extension) show minor defects, they are (in most cases) easy to repair. For repairs, consider using permanent waterproofing tape. This type of tape is available at any hardware store. For larger defects, consult a professional. An expert in this field may be able to install new lead, extending the lifespan of the skylights.

Other comments on roof opening

Regarding the roof opening (dome or skylight under construction), a critical look should be taken for any defects. This includes leaking glazing, other leaks, and/or defects in the hardware.

If double glazing leaks in the roof opening (dome or skylight under construction), visibility will become even more blurred over time. Technically, a leaky double glazing pane is harmless; the glass can be replaced automatically. However, visibility will be reduced, and the RC value will also decrease.

Non-active leaks can occur near the roof opening (dome or skylight under construction). This can be caused by the window being left open during rainfall or by condensation. If there are still (non-active) leaks, this could also be the cause of a previously repaired defect on the exterior of this roof opening. If there are active leaks, rainwater ingress or condensation could be one of the causes. In this case, there's little you can do other than carefully manage the roof opening's opening position and/or possibly improve the indoor climate to combat condensation.

Poor maintenance of the entire roof opening (dome or skylight under construction) will inevitably negatively impact its lifespan and lead to replacement sooner than usual. Overdue maintenance can be addressed by doing it yourself. You can do the following to prevent overdue maintenance:

  • Regularly grease any moving mechanical parts or spray them with penetrating oil.
  • Remove any contamination from the outside.
  • Clean the whole thing regularly.
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If the hinges and locks of the roof opening (dome or skylight under construction) or any mechanical components are not functioning properly, they should be checked (by a professional) and replaced if necessary. After that, the whole thing will usually function properly again.

If the skylight (dome or skylight under construction) is difficult to open and close, we recommend first spraying all moving parts with penetrating oil and then lubricating them. If necessary, the entire system can be adjusted so that the operation, as well as the window's opening and closing, functions smoothly and as intended.

With an acrylic skylight, if it becomes damaged or broken, there's a risk of water ingress. In that case, repair is usually no longer possible. The dome (only the cover) must then be replaced.

Would you like to make an appointment for a building inspection?

The cost of a building inspection (up to 250 m²) is only €489 including VAT. We'll conduct a comprehensive building inspection and you'll receive a building report. Do you have any questions? We're happy to help and can schedule an appointment with an expert inspector right away if you wish!

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