The recent introduction of Part O of Building Regulations has designers searching for solutions to achieve the requirements for ventilation, and many are turning to inward opening windows. But is this the only solution?
Not necessarily. Inward opening provides the most obvious solution to the key point for safe operation of windows in Part O, which means that ‘window handles on windows that open outwards are not more than 650mm from the inside face of the wall.’
However, inward opening windows have additional considerations including:
- Impact on internal floor space and position of furniture
- Window cill boards, which are a useful area for storage of decorative items or plants
- Often more expensive due to complicated tilt/turn ironmongery
Another concern for Part O is controlling the amount of heat from solar gain. Façade glazing is a major contributor of heat gained inside buildings, so architects should consider the design of window configurations to ensure they provide ventilation and limit unwanted solar heat. The easiest way to achieve this is by reducing the number and size of fixed glazed elements, and to increase the number of opening.
There are further things to consider when choosing between inward and outward opening, which will also impact the usage:
- Flexibility of ventilation solutions with lockable night vent positions, opening restrictors, and free opening on friction guides
- Handle heights <1400mm from floor level to achieve requirement of Part M4(2)
- Internal cleaning
VELFAC windows can provide solutions to all of these issues in either inward or outward opening, but crucially, the V200 System maintains the same slim sightlines for opening and fixed lights, ensuring a clean, modular aesthetic is always achieved. And because they are outward opening, there is no impact on internal area or cill board, making the internal space more usable and saleable.
VELFAC recommends early engagement with their specification team, who can assist architects in choosing the best solution for their project, providing ventilation calculations, example pricing, and solutions for restrictors or handle positions. Contact them at sales-support(Replace this parenthesis with the @ sign)dovista.com