How Many Windows do I Need For My Room?

Adding a greater amount of natural light into a new or existing living space is an essential part of any successful

 

extension or loft conversion design.

By Larry Bohan on 28 May 2019

Alongside increasing space and value, creating a brighter and lighter room is often the

 

driving factor behind most home improvement projects.

The importance

 

of daylight to our health

 

and need for less reliance on artificial lighting has come into sharper focus in recent years

 

as a result of

 

alarming findings on the amount of time people are spending indoors.

The most popular and well-known way of achieving a healthy and even flow of daylight at home is through a

 

combination of vertical and sloped

 

glazing. Less obvious, however, is knowing how many windows are needed to optimise these levels in order to really feel the benefits.

Here is an overview on best practice for daylighting home extensions and loft conversions, along with a few other ideas on how to turn your new space into the brightest, most welcoming area in the home.

How many Windows do I Need?

Be it a ground floor

 

extension or

 

loft conversion, the general rule we advise for effective daylighting is that a room's glazing should be equivalent to 15-20% of the whole

 

floorspace

 

at a minimum to

 

ensure daylight hits the whole area.

With lofts, this is achieved most easily by installing rooflights into the existing roof structure.

 

As long as headspace is no issue, adding roof windows

 

to a roof that needs no further

 

alteration

 

is

 

the less expensive and time consuming option versus a dormer extension.

A dormer loft extension might

 

be your next best option if the basic rooflight conversion doesn't offer enough head height or floor space.

 

Although the same 'floorspace÷5= glazing area required' formula is the same for

 

extensions, getting daylight right

 

can be trickier as the level of light provided by

 

big sliding doors or bifolds can be deceptive in extensions.

It is important to remember that rear extensions

 

can actually push daylight away from the original building, so complimenting your

 

vertical glazing with pitched roof windows

 

or flat

 

rooflights is key.

 

Roof windows, like those from the VELUX Group, RoofLITE and ECO+, can

 

let in as much as twice the daylight as vertical windows of the same size.

Combining pitched and vertical

 

ensures an even spread of daylight

 

at different angles, from dawn to dusk.

 

With North facing extensions, getting this

 

balance right is even more important as sloped windows can sometimes provide the only effective source of daylight.

Five Tips for Getting the Most From

 

Your daylight

Save Money with Fixed Windows

If your

 

project has already got a sufficient amount of

 

ventilation provided

 

by

 

exterior doors or other vertical glazing, opting for

 

non opening roof windows or fixed rooflights is

 

a smart way of filling the space

 

with daylight while saving a few pounds compared to the cost of manual or electric units.

Use a skylight to Highlight a Feature

By strategically positioning your roof windows or skylights in the roof you can draw people’s attention to a certain spot

 

or

 

prioritise an

 

area

 

of the room that is most used, for example a dining or play area.

Use Light Reflective Decor

 

A clever way of making a room even brighter is with white/neutral coloured walls and decorative mirrors.

 

Adding light-reflective materials will help bounce light around the room, making it even lighter and airier.

Cut Back on Frame

 

Pick modern rooflight designs with

 

next to no

 

frame, such as a contemporary roof lantern,

 

to ensure there is nothing hindering the pathway of natural light into your extension or your enjoyment of the views up above.

Add Blinds

It might seem obvious, but blinds are a must-have when too much sun starts to become a problem. In loft bedrooms and en-suites they’re near on essential, while suitable

 

extension rooflights will also

 

need blinds to reduce glare.