Oak RSJ Covers/Vaulted Ceiling/Cathedral Ceiling Hollow Beams
At Celtic Timber, sustainability is at the heart of everything we do. We source our timber from FSC and PEFC certified forests, ensuring responsible management and protection of natural resources.
We also actively contribute to reforestation and rewilding projects across the UK, planting over 12,000 trees on our own land. By choosing our products, you’re supporting a company dedicated to reducing environmental impact and preserving the planet for future generations.
At Celtic Timber, sustainability is at the heart of everything we do. We source our timber from FSC and PEFC certified forests, ensuring responsible management and protection of natural resources.
We also actively contribute to reforestation and rewilding projects across the UK, planting over 12,000 trees on our own land. By choosing our products, you’re supporting a company dedicated to reducing environmental impact and preserving the planet for future generations.
We offer a hassle-free 30-day returns policy for all non-bespoke items. If your product arrives damaged or incorrect, contact us immediately, and we'll arrange a replacement or discuss compensation.
To qualify for a refund or replacement, notify us within 30 days of receipt, and ensure the item is returned unused, in its original packaging.
Please note, return shipping costs are the customer's responsibility, except in cases of damage or error on our part.
We offer a hassle-free 30-day returns policy for all non-bespoke items. If your product arrives damaged or incorrect, contact us immediately, and we'll arrange a replacement or discuss compensation.
To qualify for a refund or replacement, notify us within 30 days of receipt, and ensure the item is returned unused, in its original packaging.
Please note, return shipping costs are the customer's responsibility, except in cases of damage or error on our part.
Please message us if you live in a highland/island area for accurate pricing.
Current lead time - Approx. 1-2 weeks. For large orders there may be a longer lead time, please get in touch with us prior to ordering for a more accurate timescale.
- Hollow oak box beam RSJ covers.
- Made of 2 or 3 (depending on your selection) kiln-dried/joinery grade oak boards invisibly joined together.
- For U-Shape Box Beams - you will receive 2 sides with the chosen "height" and one side of the chosen "width"
- Wood thickness is approximately 27mm
- Please enter the dimensions of the object that you are need to cover/the internal dimensions of the box beam.
- Depending on the width chosen and our stock availability, these boards may contain joins.
- Orders will be made up of 2000mm max length beams so that they can be transported safely via palletized delivery.
Oak RSJ Covers
RSJs (Rolled Steel Joists) are important structural elements in construction. However, they're not always built with aesthetics in mind.
Our U-Shape oak box beams are 3x high-grade solid oak boards, joined together to present a 3-sided cover for RSJs and other ugly structural steelwork.
Our L-Shape oak box beams are 2x high-grade solid oak boards, joined together to present a 2-sided cover for RSJs and other ugly structural steelwork, with a wall and a ceiling covering the other sides. You can order 2 L-Shape box beams to cover a 4 sided post
Our kiln-dried oak boards are Joinery Grade (QB2). This means that they contain fewer knots and blemishes than character-grade oak. The kiln-drying process greatly reduces the moisture in the wood, making it as stable as possible for oak.
When sent with couriers/hauliers, we may glue supports on the inside of the beam to strengthen the product for the delivery network. These will need to be hammered out prior to installation.
Finishes explained:
Contemporary finished oak RSJ covers have been planed, sanded and have had the corners rounded to remove sharp edges. This finish allows the beauty of the oak to shine through in its most natural form. 
Contemporary/Square Box Beam Finish
The Lightly Worked finish adds a light curve to the edges on the face of the beam, which can add to the beam’s character. 
Lightly Worked Box Beam Finish
Our Heavily Worked finish, is similar to the lightly worked beam but with deeper curves.
Important - Please note the following before purchasing;
As our Oak Planks are a natural product, each piece may be different in appearance and vary slightly in colour.
2000mm max. length per order for example if you ordered 4000mm length you will receive 2 x beams @ 2000mm long
Looking for something bespoke?
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.