LK, in common with all high quality manufacturers, commits continuous effort to “research & development” to ensure both its under floor heating and its plumbing systems work efficiently.
LK are advocates of harnessing “weather compensation” [either direct from the heat source or coupled to the under floor heating] to warm water under floor heating, arguing that as ufh systems are by definition Low Temperature Hot Water, it is wasteful to send “hot” water to be cooled at the mixing valve before entering the ufh pipe loops; far more efficient to send water heated to as near the design flow temperature as is practicable.
Where weather compensation can not be used, then LK ensures that room temperature control, linked to its under floor heating, is as effective as possible.
All green technology heat sources work very well with under floor heating; recently LK has been impressed by the relatively low capital costs and ever improving efficiency of “air to water” heat pumps.
The growing use of heat recovery ventilation systems, linked to vastly improved building “air-tightness” is very welcome; if heat is not wasted, it does not require replacing…
But “efficiency” will always be affected by other “building issues”, to state the obvious; a major contributor to a building’s heating requirement, and therefore its “carbon foot-print” is how well it is insulated.
Again, to state the obvious, if a building does not lose much heat, it does not require much heat to keep it comfortably warm. Likewise, if it does not gain much heat in the summer, it will not require much energy to keep it comfortably cool. Reducing the U-value of an external wall from 0.35 to 0.25, or beyond, has a massive impact on efficiencies and carbon reduction.
Part L was and is a great move forward for England & Wales, but these are minimum standards to achieve, not, as we have heard some advocate, the maximum necessary to give economy and comfort. Real economy comes from the professionals [Architects, Consultants, Engineers and Designers] “building in”, if not the maximum insulation, then the optimum insulation and ensuring their clients understand the real benefits, short and long term, personal and global, for what the client may mistakenly perceive as high initial capital cost.
Surely the right message is to “insulate, insulate, and then insulate some more…”
When we look at the practices and standards that our colleagues in Scandinavia use, we see that the intelligent use of insulation benefits all parties in the supply chain as well as the home owner and building manager.
As a result of high insulation standards our Scandinavian colleagues now often consider providing 50W/m² heat output as “over-egging” heating requirements, many LK under floor heating schemes for Scandinavia are designed at 35W/m² or below; thus condensing boilers run in “condensing mode” for longer periods and greater efficiency, heat pumps work producing improved efficiencies [COP’s] and solar panels work effectively. The Scandinavian HVAC market recognises these truths and sells the concepts with consistency and confidence to their clients.
Despite Part L1 and Part L2 being widely understood in our industry, there persist wide misconceptions elsewhere; the UK offices of LK still regularly receive requests to design projects at 100W/m² for [solid] ground floor and 75W/m² [wood] first floor “new-build” projects, even when the heat loss calculations clearly show that much lower out-puts are required. Time and time again we are told “Are, but it’s better to be on the safe side, isn’t it?” Safe side of what? This misconception is potentially very expensive for the client, requiring “over-sized” heating plant and higher than necessary running costs and, of course, a lost opportunity to further reduce carbon emissions. Plus, it misses the great benefit of warm-water [LTHW] under floor heating; that it is the occupant that benefits from the gentle radiant heat first, thus giving real comfort at lower air temperatures.
With the welcome inclusion of Oil Fired boilers in to Part L this April, yet another part of our industry will benefit and the users of oil fired boilers will see significant economies and savings.
Clearly there are other benefits for optimising insulation; since arriving in the UK, LK’s contacts with Architects has revealed widespread issues and concerns about the use of under floor heating with wood and stone floors, the vast majority of issues going back to times when insulation was considered an unwelcome additional building cost and 100W/m² really was necessary; this relatively high out-put led, in turn, to relatively high surface temperatures, causing problems. In Scandinavia, these misconceptions do not exist, with floor surface temperatures of 24ºC to 25ºC providing ample warmth and comfort, the occupants enclosed within effective envelopes of insulation. Fortunately, we have found it simple to demonstrate that modern insulation standards combined with advances in control systems also give the UK client safe, economic, comfort and warmth.
Lastly, a word about being HIP; soon it will be mandatory for vendors of houses to provide potential purchasers with Home Information Packs. I doubt any of us fully understand the impact this will have on our industry as home owners feel obliged to invest in their homes to make them “saleable” and purchasers of “new build” homes start to realise the “resale” implications and start to ask searching questions about the “biggest investment of their life”. Never before has it been so important for our industry to have the right answers and give sound advice. |