In the Glass or Tile chapter I mentioned the importance of correctly ventilating a conservatory roof, and this subject is so important that I have decided to give it its own chapter.
Building regulations requires that opening windows cover the equivalent of 5% of the floor space in a room as a minimum. Opening windows should be positioned on all elevations of a conservatory where possible, and preferably large opening windows mixed with opening clerestory windows or fanlights where the design permits. The higher the percentage of opening windows the better.
Maximizing openings gives you options as to which windows to have open and allows new air to enter the room from all directions. And with some full top to bottom opening windows you will get new air in at the lowest possible level.
Air will enter a room much more efficiently if an opening elsewhere in the same room is also open. This will enable the full recycling of the air and thus prevent it from remaining stagnant and heating up.
We all know that hot air rises, so if you only have low level openings in your conservatory then the air in the vaulted part of the roof (the hot air) will remain. Every conservatory design where possible, should include at least one roof ventilator, and on larger designs sometimes four or more.
The roof vent allows the hot air to be sucked out of the conservatory – much the same way your back door slams shut when you open the front door – this suction pulls new air into the room and is a continuous cycle even on days with little or no breeze.
North facing conservatories also need to breath properly and will benefit from having the air re-cycled in the summer so again roof vents should be included in the design.
If anyone tries to put you off and tells you roof vents might be a weak point for potential leaks, they are either using the wrong roof vent supplier or have no confidence in the product they make and sell – so find someone else!
Something that is worth mentioning in this chapter is Air conditioning.
Over the last ten years I have seen a large increase in clients wanting air conditioning units designed into their conservatory. On some designs this can really work well, but to work properly they need a room to remain sealed as much as possible. If you think you might like air conditioning you must mention this to your architect or professional designer at the very beginning as the cooler units are large and need to be designed into the building..
Tip: You should always have equal sight-lines in a conservatory so the opening windows look identical to the fixed ones. This will give you the freedom to place opening windows anywhere – without compromising the look of the conservatory.