Caravan Skylight & Roof Hatch Buying Guide

Choosing a Caravan Skylight or Opening Roof Hatch

A caravan skylight brings daylight into your living space from above. An opening skylight also provides natural ventilation, allowing air to move through the roof opening while you’re parked.

VanDIY’s SJRV skylights combine double glazing, an integrated blockout blind, flyscreen and 12V LED lighting. Three sizes suit different roof layouts. The square 400 × 400mm model uses a manual aluminium push rod with two opening positions; the 400 × 450mm and 500 × 700mm models have manual opening supported by gas struts.

Whether you’re replacing an existing roof hatch or planning a new caravan build, start with the roof opening, roof thickness and available space around the installation.

Skylights and Powered Roof Fans Serve Different Needs

An opening skylight provides daylight and natural airflow through an open roof hatch.

A powered roof fan uses a motor to move air. Choose according to whether your priority is overhead daylight, powered extraction or a combination of separate roof fittings.

The three SJRV skylights compared here include LED lighting but do not include an extraction fan.

For powered ventilation, see our SJRV Plus Roof Fan Buying Guide.

Compare the Three SJRV Skylight Sizes

The compact 400 × 450mm model suits layouts with less available roof space. The larger 500 × 700mm model provides a larger overhead glazing area where the roof structure and surrounding fittings allow.

The square 400 × 400mm model has three adjustable LED brightness levels and suits roofs 28–50mm thick. The 400 × 450mm and 500 × 700mm models suit roofs 25–60mm thick.

Nominal Size, Cut-Out and Overall Frame Size

These measurements describe different parts of the skylight:

• Nominal model size identifies the size category.
• Required cut-out is the installation opening through the roof.
• Overall frame dimensions describe the complete assembly extending beyond that opening.
• Roof thickness is the depth of the roof construction at the opening.

The 400 × 400mm model requires a 402 × 402mm cut-out. For example, the 400 × 450mm model requires a 402 × 452mm cut-out. The 500 × 700mm model requires a 502 × 702mm cut-out.

These specified clearances apply to these SJRV models. They are not a universal rule for other skylights or roof hatches.

Use the selected product’s dimension drawing when planning the installation.

Double Glazing and Daylight

All three skylights use double glazing to admit daylight while helping reduce heat transfer compared with a single-layer panel. The 400 × 400mm model has a double-glazed hollow acrylic lid.

The dome brings natural light into the caravan during the day. The integrated blind lets you reduce overhead light and improve privacy when required.

Integrated Blind and Flyscreen

Each skylight includes a pleated blockout blind and an insect screen.

The blind and flyscreen can operate independently or connect magnetically, allowing you to adjust shading and insect screening as your needs change.

Use the flyscreen with the hatch open when you want natural ventilation with an insect barrier.

Manual Opening: Push Rod or Gas-Strut Support

The 400 × 400mm skylight opens manually using an anodised aluminium push rod, with two opening positions and a secure locking mechanism.

The 400 × 450mm and 500 × 700mm skylights open manually, with gas struts assisting the lid’s movement. High-strength metal hinges support their opening assemblies.

The 400 × 450mm and 500 × 700mm models open up to 60 degrees. Allow space above and around the hatch for the lid to move without contacting solar panels, roof racks, aerials or other fittings.

Fully close and secure the hatch before travelling.

Built-In 12V LED Lighting

Integrated LED lighting provides illumination after dark.

The 400 × 400mm model has cold-white LED lighting with three adjustable brightness levels. These settings change brightness, not light colour.

The lighting requires a suitable 12V DC connection. The hatch opening is manual; connecting the lights does not turn it into an electrically operated hatch or powered extraction fan.

Roof Thickness and Installation Planning

The 400 × 400mm model suits roof thicknesses of 28–50mm. The 400 × 450mm and 500 × 700mm models suit roof thicknesses of 25–60mm.

Before selecting the position, consider:

• The roof cut-out and supporting structure.
• Roof thickness at the opening.
• Space inside for the blind, flyscreen and trim.
• Space outside for the frame and opening lid.
• Access to the manual opening controls.
• A suitable wiring route for the LED lighting.

The 400 × 400mm model has a UV-resistant ASA frame. The inner and outer frames of the 400 × 450mm and 500 × 700mm models use UV-resistant ASA material. Correct support, fixing and installation sealing are essential to the completed assembly.

Replacing an Existing Caravan Skylight

Record the existing roof opening and roof thickness, then compare them with the new skylight’s installation dimensions.

A similar-looking dome or matching nominal size does not establish compatibility. Overall frame coverage, internal clearance, fixing arrangement and lid movement also matter.

For a replacement assessment, provide VanDIY with measurements and photographs of the existing hatch from inside and outside.

Frequently Asked Questions

Can these skylights bring natural light into my caravan?

Yes. All three have double glazing that admits daylight from above.

Can I open them for ventilation?

Yes. The 400 × 400mm model uses a manual aluminium push rod with two opening positions. The 400 × 450mm and 500 × 700mm models open manually with gas-strut assistance, providing natural airflow through the roof opening.

Do all three models include a blockout blind and flyscreen?

Yes. Both are included with each skylight. They can operate independently or connect magnetically.

Is 12V LED lighting included?

Yes. All three models include LED lighting that requires a suitable 12V DC connection. The 400 × 400mm model offers three adjustable brightness levels in cold white, not three different light colours.

What roof thickness does each size suit?

The 400 × 400mm model suits 28–50mm roofs. The 400 × 450mm and 500 × 700mm models suit 25–60mm roofs.

Do these skylights include an extraction fan?

No. They provide natural ventilation through the open hatch. The electrical connection powers the LED lighting.

Is the nominal model size the exact installation cut-out?

No. The 400 × 400mm model requires a 402 × 402mm cut-out. The 400 × 450mm model requires a 402 × 452mm cut-out. The 500 × 700mm model requires a 502 × 702mm cut-out.

Are they guaranteed direct replacements for every Dometic, Seitz or other-brand roof hatch?

No. Replacement suitability depends on the roof cut-out, roof thickness, mounting arrangement and available clearance.

Shop SJRV Caravan Skylights

Explore the SJRV 400 × 400mm skylight with three-level LED brightness.

Compare the compact SJRV skylight and larger SJRV skylight.

Browse our caravan hatches, skylights and service doors for the complete range.