How to avoid being forced to replace replacement windows

Sadly, many property owners are not conversant with the current England and Wales Building Regulations, which come into force the moment any homeowner decides to replace any door or window, or indeed if creating a new builders opening or adding an extension.

To avoid any nasty surprises in the future, it is therefore important before ordering replacement windows or doors that property owners get clued up on what they can and cannot do if and when replacing doors or windows. Nowadays, trying to sell a property without proof that new products added to a dwelling fully comply with the Building Regulations, can not only slow down the sale, but potentially jeopardize it and certainly will reduce what a purchaser is willing to pay.

Proof that a new window or door complies with the current Building Regulations is provided either by your local council’s Building Control Department (i.e. when having an extension or creating a new builders opening after having obtained Building Regulatory Approval from your local authority ) or by obtaining a FENSA certificate if replacing windows or doors using a FENSA registered installer. FENSA is the Government authorised Competent Persons Scheme for the replacement of windows, doors and roof lights in England and Wales.

So, to avoid the unnecessary expense of being forced to replace new replacement windows and doors by your local authority’s Building Control Officer, it makes sense to ensure that both the products you have fitted, and your installer comply with the FENSA regulations. To avoid having the wool pulled over your eyes by a replacement double glazing installer looking to cut corners, here are some of the key facts you need to know before ordering new doors or windows.

  • You/your installer are not permitted to lesson ventilation. For example, if your existing windows and doors have trickle vents, your replacement products must also have these fitted.
  • You/your installer are not permitted to reduce the overall amount of opening vents in any window. For example, you are not allowed to replace an opening window with a fixed one, nor replace a full height side opening casement window with for example an opening fanlight over a fixed pane.
  • You/your installer MUST ensure that all replacement windows in all habitable rooms are fitted with emergency egress with “an unobstructed openable area that is at least 0.33 square metres and at least 450mm high and 450mm wide.”
  • Emergency egress “windows should be designed such that they will remain in the open position without needing to be held in position by the person during their escape.”
  • You/your installer MUST be able to prove that the replacement windows you fit can achieve a minimum of an energy rating of “C” or have a maximum combined U-Value of 1/6 W/m2K.
  • You/your installer MUST fit toughened safety glass in all windows that are within 800mm of the internal floor level or within 300mm of any external door.
  • You/your installer MUST fit toughened safety glass in all replacement doors and in all bathroom windows that are adjacent to a bath or shower.
  • You/your installer MUST fit a door to the principle entrance to a dwelling with a clear opening width of 775mm to any extension or new build home. “The clear opening width is taken from the edge of the frame on the latch side to the face of the door leaf when open at 90 degrees.”
  • You/your installer MUST fit a low threshold to the principle entrance door of an new home or extension. And if replacing a door “when the outgoing door is compliant with new build requirements the replacement shall also be complaint.”
  • Except for kitchens all habitable rooms in the ground storey should either: a) open directly onto a hall leading to the entrance or other suitable exit, or b) be provided with a window (or door) which complies with the Fire Safety requirements set out in the Building Regulations.

It is therefore wise to select an experienced FENSA registered installer to assist you in designing your replacements doors and windows to ensure that they fully comply with the current Building Regulations. The cost of having to replace brand new replacement windows and doors that do not comply will be far higher and disruptive than paying a bit more to install compliant products well fitted by tried and trusted FENSA registered double glazing suppliers.


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