Conservatory Heating and Ventilation
Conservatory heating and ventilation is an important consideration for the overall comfort of your conservatory. On sunny days your conservatory will quickly warm up and when evening falls you can use window blinds to trap the heat inside.
Natural heating can be supplemented with underfloor heating; this can be electric underfloor heating, which many people consider to be the most cost-effective, or hot water underfloor heating, plumbed into your central heating system. Like electric underfloor heating this allows you to design the interior of the conservatory without worrying about the positioning and placement of conservatory radiators whether using hot water or electricity to heat them.
You can manage conservatory ventilation simply with windows and roof vents, manually or automatically controlled. Ceiling fans also aid the ventilation in a conservatory, as will extractor fans. If planning to use these, consider installing energy-saving heat recovery extractor fans.
Conservatory air conditioning units not only keep your conservatory cool, they can also work in reverse and pump warm air from the outside to the inside.
A conservatory designer or central heating engineer will be able to calculate your heating requirements by measuring the internal volume of your conservatory, the expected heat loss through the glazing and dwarf walls and taking into consideration the direction that the conservatory is facing.
If you plan to use your conservatory throughout the year you will need to decide how to heat it most cost-efficiently.
Heat escapes via double glazed conservatory windows eight times faster than through conventional cavity walls, so choosing energy-efficient heating is more important in the conservatory than other rooms in your home.
In the summer, heating is rarely a problem except late in the evening or early in the mornings. Take simple steps to trap natural heat inside from the daytime by ensuring roof vents and windows are closed before it gets too cool and use window blinds as another thermal barrier.
Conservatory Underfloor Heating
The Romans were famous for introducing underfloor heating to their homes warm, it is known as hypocaust, from the Latin hypocaustum, from the Greek hypo under and kaiein to burn.
In 1685 John Evelyn, the famous writer and horticulturist wrote about a visit to the Apothecaries Garden in Chelsea in which he saw “… heate, conveyed by a stove under the Conservatory…”.
In those days the heating fuel would have been charcoal and it would probably need a boy tending the stove day and night to ensure it stayed alight, adding more fuel and removing the ash.
Fortunately, heating a conservatory is easier to manage today and electric underfloor heating is probably the most efficient heating option.
Alternatively, if your central heating system can cope with the additional demand and plumbing can be incorporated into the existing radiator circuit, you can choose a hot water underfloor heating system. However, this can be an expensive solution unless your central heating boiler is receiving pre-heated water from a solar heating system.
So for many people electric underfloor heating is a better option as there is no plumbing involved and all that is need is 13-amp socket nearby.
Several years ago it was advisable to use an underfloor heating system only when the flooring was ceramic or stone. Heat had a detrimental affect on wood floors, but using engineered wood that is more stable and less prone to shrinkage and warping has now largely solved this problem.
One of the great advantages of an underfloor heating system is that it is invisible and will allow you to design the interior of the conservatory unrestricted by the problems positioning wall-hung radiators.
If you choose to use radiators plumbed into your central heating system to heat your conservatory, remember that you may have to run these on cool spring, summer and autumn evenings when the central heating system is normally closed down. If this is the case, you may prefer to find an alternative method of providing extra heat when it is needed.
Electric radiators can be a better solution and as they don’t have to be plumbed in to the central heating system they are easier to install. They also heat up rapidly, so you will quickly feel the benefit of their warmth.
Whatever type of heating you choose, ensure that it is thermostatically controlled within the conservatory so that you are not wasting energy.
Maintaining good conservatory ventilation allows you to enjoy a comfortable environment throughout the year. This is not just important for you, your family and guests; if you have plants in the conservatory moisture in plant pots can evaporate very quickly and the plants can quickly die.
In Building Regulations 2000 you’ll find guidance on the minimum ventilation requirements for new conservatories with a floor area over 30m². Ventilation rates are given plus advice on the positioning of controls. Further advice is supplied on the ventilation rates for an existing room adjacent to the conservatory especially when the door(s) adjoining this room are closed.
A Kitchen Conservatory will require a greater amount of ventilation to allow for the use of water and cooking appliances within it.
Taking care of conservatory ventilation in the summer is largely about taking sensible precautions to ensure adequate ventilation. Heat rises, and so the conservatory design should include ventilation points on the roof of the conservatory or at the top of windows. To create a flow of air you will need to draw colder air into the conservatory. If you have a South Facing conservatory attached to a north facing room, opening the bottom of windows in this room will create a draught of cool air into the conservatory.
Conservatory Roof Vents
Conservatory roof vents must provide good sealing against rain and wind. British Standard 5156 covers the use of glass on sloping roofs, including wind and impact testing. Roof vents are an effective way to control your conservatory heating and ventilation.
You can open and close conservatory roof vents manually or electronically. The traditional method uses a Hook & Pole to manually crank the roof vent open or shut; it is often the most attractive solution as well as there is no mechanism to install. Electronic controls will need wiring to a wall-mounted switch or remote control unit. If you are away during the day, you may wish to make the vents automatically via a digital control system that adjusts opening and closing to maintain a pre-determined temperature in the conservatory and close the vents completely if it rains.
Roof vents can also include a security locking mechanism that prevents them from being opened from the outside.
Conservatory Ceiling Fans
Ceiling fans help you save on winter heating bills and summer air conditioning if you have it, by using the warm or cool air already in the conservatory more efficiently.
During the summer a ceiling fan can aid cooling by drawing air towards open roof vents. In the winter when the roof vents are closed and by reversing the direction of the fan, they can re-circulate warm air trapped at the top of the roof downwards.
Depending on the size of your conservatory you can choose to install one or more ceiling fans. For efficiency ensure you specify fans that run at variable speeds. Fans with built in lights also save having to duplicate untidy electric wiring along roof beams.
Conservatory Extractor Fans
Using an extractor fan allows you to make frequent changes of air in the conservatory quickly or slowly, depending on the speed setting of the fan. Modern extractor fans are much quieter than they once were and are virtually silent even on medium and fast settings.
Although they are very efficient in the summer using one in winter will send lots of expensively heated air into the garden, so a better alternative is to install an environmentally friendly heat recovery extractor fan. These can recover 70-80%, or even more of the heat that they extract and return it to the conservatory.
If you are planning a kitchen conservatory, any extractor fans you use will need to be of a higher rating as they have to manage the extraction of condensation, cooking smells and heat from ovens and stoves.
Conservatory Air Conditioning
An air conditioning unit can also make an excellent conservatory heater. This is because its heat pump can take any warm air from outside your conservatory and direct it inside.
However, it is unlikely that it will be able to provide all your heating needs especially in the winter and you will need additional heating sources on cold days.