Kitchen Extensions
Tuesday, 15 April 2014 00:00

Everything You Needed to Know About Underfloor Heating For Your Conservatory or Orangery

Everything You Needed to Know About Underfloor Heating For Your Conservatory or Orangery

Cold feet from freezing floors, the bane of early mornings! It draws the heat out of your body faster than the milk isle in Waitrose, causes one to play hopscotch from rug to rug and, worst of all, makes a room feel unwelcoming, even if the radiator is glowing! It is especially pronounced in the Winter, but even in Summer a flagstone floor can send a chill running up your spine. 

This is a problem, yes, but not one that is insurmountable, far from it - in fact there has been a perfect solution being installed in homes and public buildings since around 5,000BC, yes, that’s seven thousand years we’ve been utilising heating systems to warm our floors. The Romans are often credited with the invention, but it was in Korea that the first heated stone flooring was utilised.

What is an Underfloor Heating System?

An underfloor heating system (UFH system), simply put, changes the radiation surface for the room from a radiator plate on the wall to the floor material itself. This has several advantages over the conventional radiator heating method, but isn't without its drawbacks. I’ve detailed the pros and cons at the end of this article.

Two System Types:

An UFH system can be classed as either “wet” or “dry”. This differentiation stems from the method by which heat is dispersed into the flooring surface. In a “wet” system a pattern of PVC pipes is laid out under the floor evenly and a solution of water and anti-freeze is pumped around the network. If this solution is heated (by a boiler or a solar/geothermal source) then the floor will warm until the thermostat cuts the flow of hot fluid. In some systems this process can be reversed so that heat is drawn from the floor and transferred to a “heat sink” or fluid temperature conditioner which will give the floor a desirable cool sensation in hot climates. 

The other method you may wish to investigate is a “dry” system that makes use of an electrically powered heating element that is embedded into a mat and rolled out under the floor. This dry system works using the same principal as any electrically heated device in that a current is passed through the element so that it produces heat. This system obviously can’t be used as a cooling system.


Wet Vs. Dry Under Floor Heating Comparison

Wet UFH System

Dry UFH System 

Requires a large amount of floor disruption, measuring and will often affect floor height. Is best installed before a floor is laid (as in a new conservatory or orangery)

Can be installed under any surface, even linoleum, carpet or rugs. Minimal disruption, with little adjustment to floor height. 

High initial cost, both for system and installation

Cheaper initially, both for system and installation

Can be hooked up to solar water heating or geothermic heating systems to take advantage of renewable energy, which saves on cost and reduces the environmental impact of heating your glass house

May be connected to a time-of-use metering system so that the thick flagstones are heated at night on a cheaper electricity tariff to save on running costs. 

Large control panel 

Smaller electrical control box 


No Radiators on the wall - This will allow every available wall to be used to put furniture against/ allows for more flexibility in interior design (something very important in conservatories and orangeries where a lot of the room edges are likely to be walkthroughs and open arches etc. 

More family friendly - Conventional radiators are a big hazard and source of concern for parents with children as they pose both a nasty collision risk and burn hazard. 

More perceived warmth -  Because the heating surface is the whole floor space , there are no hot (or cool) spots, heat is evenly spread bottom to top of the room. This makes the room feel warmer, and generally more comfortable. In addition, there is no loss of heat through conduction (feet on floor) which leads to an added sense of being “cozy”.

More Robust - Allows the use of “cold feeling” floors such as tile, marble or flagstone that are harder wearing and more hygienic/hypoallergenic (which is a great bonus for asthma sufferers)

More Energy Efficient: Because the UFH system runs at a “warm” temperature rather than “hot” like radiators require, this allows the boiler to run more efficiently. 


Cost Of Installation - The cost of underfloor heating is the obvious downside, and most of this inflated cost is due to the difficulty of installation. This is particularly obvious when installing “wet” UFH systems, though even “dry” electrical systems have their own costs associated (a qualified electrician is required for instance)

Difficult To Install In Existing Room - Because an underfloor heating system needs insulation under it to prevent the heat from simply conducting into the ground it can require the floor to be raised in some instances to make room for the extra padding. This is why it is preferable to instal it in a new build, rather than retrofit it in an existing property.

Wrap Up

While it may seem like underfloor heating is a complicated and expensive proposition, it adds a great deal of comfort and flexibility to a room; it provides more space, less hazards, less energy consumption and, last but not least, warm toes. Its a brilliant addition to any orangery or conservatory project that will make the space even more usable, comfortable and practical than it already is. 

    A highly professional and delightful end result. My wife and I could not be more pleased.
Mr & Mrs Raffin, Guildford