HOW TO GET YOUR WINDOWS APPROVED BY YOUR BUILDING INSPECTOR
Although there are certain freedoms when it comes to the design of your windows, you’ll need to ensure that it meets the building regulation requirements specific to your location. Here are a few things you'll need to look out for:
Any glass below 800 millimetres from floor level will need to comply with barrier loading if there’s a change in level outside over 600 millimetres. This is to ensure your window will protect any occupants from falling. The barrier loading can be reviewed by your engineer, or your window company can appoint an engineer on their behalf to review as an additional service. Either way it’s going to be an added cost.
It's also worth noting that any openable windows under 800 millimetres from the floor will need to feature some form of safety mechanism to prevent falling. In England, This could be done through mechanisms such as window stays or locks and is subject to building control approval. Alternatively, you can provide protective barriers, such as Juliets, which act as a safety barrier and can also be a key design feature of the room they serve. Protective Barriers are the only method accepted in Scotland. Juliet balconies affect the operation of the window or door and some manufacturers now offer a fully fitted glazed barrier as part of the unit. Meaning they can operate fully while maintaining safety features and minimise the impact on external finishes as you don’t need to retrofit any external barrier into your newly clad building.
Your building inspector will also be checking for any trickle vents (if part of the ventilation strategy) to ensure they have been placed correctly and are the right size. Always ensure the free area requirement of the vent can be placed on the window, some units are too small to achieve the minimum standard and the vent fitted won’t be enough to achieve the rate for that room, causing remedial action on site to achieve a compliant ventilation strategy.
If you are building close to a boundary, there may be restrictions on spread of fire and a fire rated unit might be required. This will be raised at design stage with your architect and needs to be considered in the costings when obtaining quotes.
Lastly, always check your planning conditions, some windows placements can cause concern for overlooking and will need to have obscure glazing fitted to satisfy planning. This again needs considered at costing stage to ensure all elements to meet the design intent are considered.
THE COST OF WINDOWS AND HOW TO SAVE MONEY
When it comes to the cost of windows for self-build, it’s completely dependent on the size, materials, location and number of windows you require. In our 15 years of assisting self-builders realise their dreams, we’ve seen costs range from £30,000 to close to £300,000. Don’t forget to factor in your installation costs when budgeting, too.
Windows are expensive, in fact, they’re going to be your most expensive feature behind the kit itself. If you’re looking to get the costs of your windows down, there are a few methods you can implement
- Stick to the manufacturing constraints and avoid bespoke work where possible
- If you’re planning for a massive feature window, split it in two to save money on the glass panes
- Pick from standard colours and finishes, opting for a non-standard finish can add costs
- Consider alternative material options for your window frame
- Collect different quotes from window suppliers in your area to find the best value
- Consider rationalising different unit sizes, running the same unit size through the factory can help efficiencies at production stage
- Consider salvaging a disused window from an older house. You can browse for these online or visit a salvage shop, but be aware that older windows may not meet the required u-values
WHEN SHOULD I ORDER MY WINDOWS?