Select the joist type you are working with for compliant downlights
Regulations and Testing
The Importance of Compliance
It is important to note that unlike traditional or open web joists, one test with one i-Joist manufacturer does NOT give you automatic approval with any other manufacturer.
However it is also acceptable to NHBC Building Control to use the test to demonstrate compliance for other engineered joist floors where the key elements of the test are the same or better. These elements would include:
1. Joist type i.e. engineered joist or metal web
2. Joist size including the central web thickness and grade of board
3. Spacing of joist
4. Thickness of plasterboard
5. Density of downlighters
In addition, you would need to ascertain that the downlighters installed are the actual model that has been used in the test.
Fire Testing
Common Engineered Joist Types
Timber Engineered I-Joists, sometimes known as I-Beams, are comprised of a top and bottom timber flange combined with a tall vertical OSB (Oriented Strand Board) web:
- They are strong and lightweight, with enhanced rigidity
- High strength-to-weight ratio for easier handling and on-site installation
- Can be cut to required length on-site and installed more quickly
- Not prone to shrinking or warping, resulting in a quieter floor construction
- Can be manufactured in greater lengths, reducing the need for columns & beams
- Allows for larger spaces, satisfying the trend for open-plan living areas in homes
Metal Web Joists are constructed with a top and bottom stress graded timber cord, plated together with high strength open metal web sections on either side of the top and bottom timber flanges:
- Have an open central section for ease of installation of services
- Different lengths available to allow for longer spans
- Ideal for open-plan spaces within residential buildings
- Less timber means less shrinkage
- Manufactured to length off-site
- Timber cords should never be cut or drilled on site
- The metal webs should never be cut or removed, as this will reduce strength
Softwood joists are ideal for smaller projects, such as extensions, small dwellings or where relatively short spans are involved.
- Traditional method for building floors using solid timber
- Strength Grading of joists is done by machine to British Standard EN 14081 to classes C16 or C24
- There are actually 12 Strength Classes available in Europe, but the UK mainly uses C16 and C24
- The Strength Class of the joist is very important when determining which joist to use for your project. It will help you identify which joist dimensions to use for a particular span and loading situation
I-Joists are most commonly found in new build properties. Due to the reduced amount of materials used
in the joist, the product can experience a quicker burn through rate which is why it is essential that the
fire rated downlights and joist have been tested together.
Metal Web Joists, or Posi Joists as they are also known as are another new type of joist. The joist includes a combination of timber but also steel web which allows the joists to be used over a larger area.
| Product | SKU |
| R6™ | AU-R6 |
| R6™CS | AU-R6CS |
| R6™CWS | AU-R6CWS |
| R6™CWS | AU-R6CWSBF |
| R6™ | AU-R6FF |
| R6™CS | AU-R6CSFF |
| R6™CWS | AU-R6CWSFF |
| X7™ | AU-X7 |
| CX7™ | AU-CX7 |
| MPRO™ | AU-MPRO1A |
| MPRO™ | |
| A6™PRO | AU-A6PRO |
| A6™PRO | AU-A62PRO* |
| A6™ | AU-A6 |
| A6™ | AU-A62* |
| A4™ | AU-A4 |
| A4™ | AU-A42* |
| E8™ | EN-DE8 |
| E6™PRO | EN-DE6PRO |
| E5™ | EN-DE5 |
| EFD™PRO | |
| EFD™PRO | |
| EFD™ | |
| EFD™ | |
Solid Timber Joists are traditionally found in existing domestic floor construction and are manufactured from timber only.
| Product | SKU |
| R6™ | AU-R6 |
| R6™CS | AU-R6CS |
| R6™CWS | AU-R6CWS |
| R6™CWS | AU-R6CWSBF |
| R6™ | AU-R6FF |
| R6™CS | AU-R6CSFF |
| R6™CWS | AU-R6CWSFF |
| X7™ | AU-X7 |
| CX7™ | AU-CX7 |
| A6™PRO | AU-A6PRO |
| A6™PRO | AU-A62PRO* |
| A6™ | AU-A6 |
| A6™ | AU-A62* |
| A4™ | AU-A4 |
| A4™ | AU-A42* |
| MPRO™ | |
| MPRO™ | |
| MPRO™ | AU-MPRO1A |
| MPRO™ | AU-MPRO2A* |
| MPRO™ZX | AU-A1ZBMPRO1ZX |
| E6™PRO | EN-DE6PRO |
| E8™ | EN-DE8 |
| E8™ | EN-DE82* |
| E5™ | EN-DE5 |
| E5™ | EN-DE52* |
| EFD™PRO | EN-DLM981X |
| EFD™PRO | EN-DLM982X* |
| EFD™ | EN-DLM482 |
| EFD™ | EN-DLM484 |
| EFD™ | EN-FD101* |
| EFD™ | EN-FD102* |
| EFD™ | EN-FD103 |
Fire Rating Explained
30, 60 And 90 Minute Fire Resistance Periods
Aurora’s Fire Rated Downlight ranges are 30/60/90 rated* as standard, providing complete product confidence.
Domestic properties have different requirements for periods of fire resistance, depending on the height of the top floor above ground level or the depth of a basement.
See the following table for guidance:
