How to achieve a constant temperature in your self-build
The modern home is a space which needs to perform on so many levels and there is an increasing demand to create a high-performing one which provides us with all kinds of comfort levels.
Today, we’re seeking more than just the basic standards, especially when it comes to comfort and well-being in our home. From sales of activity trackers to the growing interest in mindfulness and other stress-relieving activities, consumers are becoming increasingly concerned with health and well-being.
It’s little surprise then that the discussion around well-being has become firmly embedded in the construction industry, with occupant comfort becoming a top priority.
As a self-builder it’s likely you’re on a quest to create the most comfortable home possible. The joy of self-building is the flexibility and freedom it provides; by carefully planning your layout, design, architecture, materials, and systems you can create a consistent and comfortable temperature in your home.
Designing for comfort is an important element to a build and discussing this from the outset with your architect can help to specify the best choices for materials, products and cost involved.
Creating a building that is well insulated and ventilated with a comfortable and stable temperature indoors and minimal heating requirements – that’s what thermal comfort is all about. How exactly do you achieve this?
Passivhaus design
Passivhaus, which means passive house in English, refers to buildings which have embedded energy efficient design standards to maintain a constant temperature.
To achieve the Passivhaus Standard in the UK typically involves showing accurate design modelling using the Passive House Planning Package (PHPP), very high levels of insulation, extremely high performance windows with insulated frames, airtight building fabric, 'thermal bridge free' construction and a mechanical ventilation system with highly efficient heat recovery.
All of this results in a comfortable, low energy or energy-efficient building helping to reduce heating costs and emissions to a fraction of current standards.
Upfront costs on creating a Passivhaus or an eco self-build are higher than a ‘standard’ new build but there are significant costs savings and energy savings to make in years to come.
Installing a mechanical ventilation system
A controlled ventilation system, or a mechanical ventilation heat recovery system (MVHR), can provide fresh incoming air and is an economical solution to heating your home during the winter months. It is a huge contributor to meeting the rigorous Passivhaus standards.
But in order for a MVHR system to work effectively a new home needs to be suitably airtight. Why is air tightness so important? Well, if you want to achieve a thermally-efficient home then air tightness can stop heat from escaping and draughts from entering.
Achieving a reasonable level of airtightness in new buildings is a mandatory requirement of Building Regulations Part L. Air leakage is a significant cause of heat loss in a building and therefore a major contributor to energy efficiency. MVHR experts agree that this system requires a minimum air tightness of 5m3/(h m2) at 50 Pa to be most cost effective.
To meet these standards and create a comfortable home, self-builder John Pryer installed an MVHR system in his four-bedroom home in Bedfordshire. After living in many different types of properties – new builds to Victorian semis – John understood all of the elements that created an uncomfortable home. He wanted an air-tight, energy-efficient home and he realised that installing an MVHR system was a solution to creating a ventilated, comfortable home.
John said: “The MVHR system provides fresh filtered air into a building while retaining the small amount of energy that has been used in heating the building. In our previous houses you’d have to open windows at night to cool the room down and find yourself waking up a bit chilly. We like the constant temperature.”
Maximise solar gain
How else can you create a constant temperature? Consider layout to maximise solar gain. Maximise the use of glazing on the south side of your building to increase solar gain, it will also help to reduce the need for space heating throughout the home. While this is key to reducing energy demand, be careful of too much solar gain as this could cause overheating. The best layouts will offer the opportunity to cross ventilate by opening windows and internal doors to create an air flow from one side of the home and out of the other.
Select the right materials
Choosing the right materials for your home is a crucial part of your self-build journey, helping you to build a dream home that is sustainable in the long run. The materials you choose will impact on costs, comfort, performance, and the finished look of your home. Consider selecting thermally efficient building materials such as timber, which does not store energy (heat), and allows the home to cool down quickly after dark - reducing or eliminating the need for air conditioning. Insulation materials will pay for themselves through reduced power bills in just a few years. There are many options and what you choose will depend on many factors, particularly if it is used in walls or the floor. Some options include glass fibre, mineral wool, and sheep's wool.