Underfloor heating and radiators

Air Source heat pumps can efficiently use radiators or
underfloor heating to distribute heat around a property.

New build properties:

New build properties are well insulated and therefore hold the heat better. This means the emmitters ( radiators / underfloor heating) can run at a lower temperature, typically 35-45 degrees. A lower flow rate will mean less cost as long as it is capable of satisfying the call for heat ( thermostats).

Many new build properties choose to go with underfloor heating on the ground floor and radiators on the first floor. There are a few reasons for this:

Ground floor underfloor heating is a low priced option because it can be stapled to the rigid insulation. The concrete screed over the pipe retains the heat well. Radiators on the first floor wok well because they emit heat straight into the room as oppose to beneath wood and or carpet which acts as an insulator and means the underfloor flow temperature must be higher (50+ degrees) similar to radiators. Further to this underfloor heating is at least twice the price on the first floor as oppose to a ground floor pipe and staples solution, the increased cost is down to the floor spreader plates ( overboard).

Existing properties

Existing properties often have radiators already in place. Once the heat loss is complete we know what the loss is in each room and can satisfy it with a radiator accordingly. Radiators will often be larger than your existing radiators because of the lower flow temperature from the heat pump.

Harvest Verdict

New build – use radiators upstairs and underfloor downstairs, its economical and has a very high efficiency.

Retro fit ( existing build) – Upgrade existing radiators as per the ‘Heat Loss Report’

Don’t Like radiator: Use underfloor heating on both floors but be ready for a large uplift in cost.

Whether you choose to have radiators, underfloor heating or a combination of both, careful design is key.

Our main concern is ensuring there is no hindrance to the heat pumps efficiency.

If the output for an emitter is too low then you run the risk of not having sufficient heating at the coldest times of the year.

The Heating

As air source and ground source run on lower temperatures radiators for heat pumps need to have a higher output. This can mean larger radiators or a different type of radiator better suited to lower flow temperatures.

We aim to achieve the lowest, reasonable flow temperature which translates to high efficiency and low running costs.

We offer both first and second fix plumbing for central heating systems.

The Power flushing

A power flush is a great way to clean out the pipework even if it is brand new. A power flush will minimise future corrosion by removing and preventing sludge build up. Maintaining the water in the system can vastly improve the efficiency of your heating system and any heat source attached to it. It is important that an inhibitor is left in the system to help prevent corrosion.

Power flushing is a service we offer all retrofit and new build properties.

Choose an underfloor heating expert.

Underfloor heating covers a large surface area and ultimately allows you to run the underfloor at lower temperatures than radiators, reducing running costs and increasing comfort.

The flow temperature required to run underfloor heating is around 35-45°C depending on how well your property is insulated.

The Design

We design the underfloor to a plan and a specification that will provide the right level of heat for the room. We produce a design for your approval before the date of install. The design is vital as areas under baths, showers, fitted wardrobes and fireplaces are avoided but need to be compensated for in other areas. All of the pipework will run back to a manifold at a destination agreed by you.

The Heat Losses

At Harvest Cornwall we don’t specify by rule of thumb we carry out a room by room heat loss which illustrate exactly how many watts are needed to meet the heat demand for each particular room. This can often mean that closer centres are needed, typically at 150mm. By carrying out a heat loss report we will be able to offer different running temperatures that will lower your running costs and make your system run very efficiently.

The hybrid – underfloor heating & radiators

Underfloor heating is more expensive than a standard radiator system and for this reason many of our clients have underfloor downstairs and radiators upstairs. Most households spend the majority of their time downstairs in warmer temperatures of 21°C, whereas upstairs in bedrooms, design temperatures are slightly lower at 18°C. Radiators upstairs and underfloor downstairs can be a very cost effective and resourceful combination.

The ground floor preparation

Nine times out of ten the ground floor will have a staple system. This is a plastic hook with a barb that pins the underfloor heating to the insulation through the membrane. It is pushed into place by way of a large staple gun.

The builder will carry out these steps prior to our engineers arrival:

Insulation – the floor must be insulated before we can staple underfloor pipework to it.

Membrane – a thin membrane will be needed to prevent screed slipping between the insulation.

Expansion strip – this will be needed on the outside to absorb any expansion from the screed.

Once the above has been completed, Harvest Cornwall install all of the underfloor heating to an approved drawing. It will be filled and left pressurised from the manifold.

The final stage is the screed. This will be poured over the pipework and left to dry. The general rule is 1mm per day drying time.

The thermostat

Control of the underfloor is slightly different to conventional heating, this is because each zone or room can be controlled individually via a thermostat. Our programmable stats mean different temperatures can be achieved in each room, rather than one temperature running throughout the house. We supply programmable thermostats that can be controlled both in the home and remotely from your computer, tablet or smart phone.

For a quotation and consultation on underfloor heating contact the office.