Tag Archives: airtightness

  • The Healthy Home Explained

    The Healthy Home

    In our view, a healthy home is   ‘one that incorporates healthy design elements, non-toxic building materials, and proper construction techniques. It "breathes", emits no toxic gasses, and is resistant to mould and decay.

    Here are our top tips when designing a healthy building.

    • Choose a simple build system
    • Use natural and non-toxic materials
    • Make the best use of natural light
    • Ensure adequate ventilation
    • Ensure that all building elements are compatible
    • Use a breathable vapour open system
    • Make the structure do the work
    • Take a whole-house approach to design
    • Include the end-user in the design and build process

    Without a doubt, it is the control of moisture and the ventilation of the building that sits at the root cause of most building decay. We also have a huge issue with applying healthy principles to the biggest issue of all refurbishing existing buildings.  Often in these cases, the prophylactic principle should be applied, where some anticipation of problems such as damp penetration can be mitigated by choosing materials that can hold onto moisture and let it go later (drying out) or at least minimise or contain the problem. The issue with a more synthetic and hermetic approach is that such problems can often remain hidden deep within the building structure for a long time and on discovery lead to costly and extensive repairs.

    To apply healthy principles to any building project you first need to appreciate that the standards by which most UK construction is governed (and built to) do not account for the ‘health’ of a building in all but the most basic ways. So don’t expect a building that meets Building Regulations to be healthy.

    To describe an unhealthy home can be more effective at persuading us to adopt healthy principles. We will all recognise the description of an unhealthy building as one that fails to control the internal environment leading to partial, then increasing, early decay of the building fabric in turn leading to mould growth, rot and a failure of the element(s) to physically perform, the description would further include the use of toxic chemicals in materials and the resulting expulsion into the air of these toxins over time, and it would include the use of materials that contain allergens.

    Now most of us will recognise (and probably have experienced) the symptoms of poor building health but it is surprising how many of the houses built today have this very low on the agenda of considerations. The consequences of damp and unhealthy buildings can mean the aggravation of conditions like asthma, in the UK this is a real problem where 1 in 6 people have asthma a massive increase since the stable base in the 1970s with almost 2000 deaths per annum and 75,000 hospital admissions the cost to the state runs into £billions; most of this is directly linked to dust mite faeces which in turn is directly linked to the relative humidity in houses, (as you find in an unhealthy house) other moulds, bacteria and diseases present in the same conditions are also linked to asthma.

    The main contributors to poor building health are the following

    • Water ingress
    • Condensation
    • Failure to control internal moisture
    • Poor build quality
    • The use of toxic materials
    • Poor ventilation
    • Material degradation over time leading to performance failure (e.g. air leaks)
    • Poor design

    You can see that it is not only the absence of harmful environmental characteristics but also the presence of beneficial ones that define a healthy building. Designers should begin by avoiding harmful elements and attempt to incorporate supportive beneficial ones. This is why the inclusion of items such as natural light, ventilation and acoustic insulation is as important as layout and functionality in the whole-house approach.

    Real progress is only made when the builder and future occupants work closely with the building’s designer to ensure that all these issues are addressed within the context of how the building is intended to be used.

    Thankfully a lot of the approach to building healthy homes is common sense and can be summarised in a few simple principles

    • Choose simpler building systems they are more failsafe
    • Manage moisture by creating a breathable shell to provide a means for managing and buffering variations in moisture
    • Include natural materials in many applications these will outperform synthetic ones.
    • Be involved at every stage

    As highlighted by recent events the toxicity inherent in our building materials can be a lethal problem especially in the case of fire, one of the most important materials used in the construction of a building is insulation, but can your choice of insulation really affect your health?

    A well-insulated house or office will protect your health, comfort and lifestyle but how many of us know and understand how to achieve this?

    How we select insulation needs to be about having a real choice and for specifiers to be equipped with the right knowledge to compare materials on a like-for-like basis.

    To design a well-insulated building, you need to make informed decisions throughout all phases of a construction project to ensure your building performs as you envisage as mentioned above.

    However, selecting the right insulation is about more than just reaching building regulation compliance or ‘keeping in the heat’. It’s about ensuring a building protects its occupants’ entire well-being and comfort in the following ways.

    How well does insulation keep the heat out?

    In the UK, thermal insulation to protect from the cold is essential, particularly given ever-increasing energy costs. However, as demand for usable square footage of buildings increases, basement and loft conversions are the routes many now take. However, these parts of a home or office, are the spaces most prone to extremes in temperature. They, therefore, need more thought – i.e. how do you keep a space warm in winter but, for a loft, how to keep it cool come summer.

    Compared with synthetic insulation materials, wood fibre insulation has a much higher density. This higher density means that natural insulation makes for a better heat buffer as the high midday temperature will only reach the internal side and be lost at night when the temperature is already cooler outside.

    Littlepits 5 bedroom detached house, timber frame Certified Passive House Plus Littlepits is now one of the most airtight houses in the UK at 0.07 ach @50Pa. Shortlisted for the Alliance for Sustainable Building Products Awards 2019 (Excellence in Sustainability).

    How a building’s lack of breathability is hurting our health

    A breathable structure is one that allows the passage of moisture.

    With 90 per cent of all building construction problems associated with water in some way, breathability is essential in measuring a building’s performance and preventing the accumulation of harmful water within the building’s fabric.  These are fundamental in reducing health risks from mould, mites that those suffering from respiratory illnesses such as asthma and chronic obstructive pulmonary disease (COPD) are particularly susceptible to.

    For effective breathability, there are four essential components that need to be considered:

    • a moisture pathway
    • a driving force
    • a sorptive fabric
    • vapour control.

    Natural fibre insulation is most effective as it suppresses potentially harmful water by binding and releasing moisture which helps regulate humidity levels as the moisture moves.

    Easy-to-fit insulation

    A well-designed building takes into consideration how a material performs throughout the building’s entire life cycle. This includes ease of installation. Steico’s wood fibre insulation is simple and easy to fit (either packed or friction-fitted), eliminating installer error, keeping construction programmes, tight and costs, low.

    How sustainability will save you time and money

    While all insulation is helping the environment by limiting energy being burnt for heat, natural fibre insulation materials are comparatively more robust. This means that when it comes to disposal, they can be composted – i.e. no specialist waste facilities or landfill. Throughout their lifecycle, they will additionally have a much lower, and often, negative carbon footprint.

    More than just protecting your home from fire

    All insulations will meet fire safety standards, but this is a minimum rating. The key differentiator between natural and synthetic is that natural insulations will prevent the spread of fire and if burnt, will not give off toxic fumes such as cyanide as polyisocyanurates (PIR) might. See article link below to ASBP Healthy Buildings or Toxic Buildings?

    Will the house be standing in 100 years?

    Condensation is one of the costliest risks to buildings causing huge maintenance repairs and structural damage. Natural materials are better able to absorb and release water whilst remaining dry meaning it is better able to protect from and buffer moisture thereby becoming a key part of healthy living.

    Comfort for occupants

    When selecting insulation for a building, there are implications for the health of the occupants, the structure of the building, its impact on the environment, its acoustic properties, durability and carbon footprint.

    Cancelling out the noise for a peaceful night’s sleep

    The higher density of natural insulations - such as wood fibre - makes them better at reducing noise. Sounds external to the building, such as traffic or music, as well as those from within the building, through walls and ceilings are attenuated better by wood fibre than synthetic equivalents. In providing better protection from acoustic pollutants, occupants often report a building as being more restful and relaxing thereby encouraging better mental health.

    When a building is well-designed and well-built, occupants should be at their peak comfort. With the average person spending approximately 80% of their lives in enclosed rooms, an occupant’s well-being is imperative. Therefore, the products used to achieve this should cover all the issues affecting a building’s construction, its impact on both its occupants and nature.

    Further reading

    ASBP Healthy Buildings Conference summary of key points, https://asbp.org.uk/asbp-news/healthy-buildings-or-toxic-buildings

    Read the expert’s view on healthy buildings including Professor Stephen Holgate CBE, Clinical Professor of Immunopharmacology at the University of Southampton and co-author of The Royal College of Physicians ‘Every breath we take‘ report, who explains why poor quality air is a lethal problem that affects us all, Consultant, Clinical Psychologist at UCL, Dr Sarah Mackenzie Ross who looks at the rapid rise in new chemical entities in our day-to-day environments and the consequences on our health, CIBSE’s Head of Sustainability Development Julie Godefroy who questions the role of Building Regulations in delivering healthy buildings and Professor Anna Stec, fire toxicity expert from the University of Central Lancashire who looks at the potentially fatal effects when plastics in the home burn.

    Visit

    www.asbp.org.uk for more on sustainable building products

    Visit our Protexion campaign page:

    'Protexion' is a joint campaign by Ecomerchant and Steico UK to promote better designed and better-built homes. It aims to champion the benefits of using natural insulation products to create healthy buildings you can learn more by clicking this link  www.ecomerchant.co.uk/protexion

  • The worst building you can build by law

    There is mounting evidence to suggest that buildings that are being designed to achieve thermal performance standards, including standards set out within the current UK Building Regulations, are in some cases consuming in excess of 70-100% more energy than the predicted values. Plus, some would say more worryingly, that the Building Regulations do not set an adequate base level of performance and facilitate the delivery of many buildings of poor quality into the UK housing market
  • 2019 the year of healthy building

    All buildings should be built with the occupant's health and comfort in mind, but much of what is built today falls short, we lack any regulatory requirement to deliver healthy buildings so it's down to customers to demand better, fortunately, there are plenty of people and businesses that can show us how.
  • A brief history of Building Regulation U-Values – with examples

    The age of your house is a fairly reliable indicator of its likely thermal efficiency especially if no upgrades have been made to the fabric of the building – although many houses have been extended or otherwise significantly modified over the years. Over the last 50 years, the level of insulation required in Building Regulations has changed drastically to reflect both the need to reduce heating bills and increasing demand for comfort from homeowners. Here we consider how insulation levels have changed and what difference it has made to energy use.
  • Designing and building with natural insulation materials

    The best buildings are life-enhancing and support our physical and mental health. Great design and healthy products enable the delivery of a healthy internal environment - meaning good indoor air quality, natural lighting as well as excellent thermal and acoustic comfort. In order to do this, we have to ensure we practise good decision making which requires an informed and holistic approach. Products that are low embodied carbon, natural, non-toxic, and healthy such as natural insulation have an important part in delivering better buildings.
  • What exactly is a VCL?

    One of the most commonly used, and widely recognised, acronyms in construction is VCL, which stands for vapour control layer. A VCL is a critical building component designed to protect the building from potential degradation (or poor performance) by managing the passage of water vapour within a building structure. In other words, it is used to manage condensation risk. Condensation is formed when warm moist air condenses into a liquid on contact with a colder surface. A vapour control layer is typically installed on the internal side of the insulation to control the passage of warm moist air (water vapour) entering the structure. However, as a simple acronym, there is a problem because in most applications a specific level or type of performance is required, as a ‘catch all’ acronym VCL is wide open to error.
  • Adhesive tapes: how do they work, what should they be able to do, and what can they do?

    Adhesive tapes are used as bonding aids in a wide range of applications in the creation of airtight building envelopes. Several hundred metres of tape is often used on a single building! Adhesive tapes have become established as bonding agents for these applications (just as nails are the standard solution for timber structures). They have to fulfil their functions for a number of decades to ensure that the building in question fulfils the standards expected by the energy consultant and by the building client. This article provides an overview of adhesive technology and the key properties of adhesive tapes typically used in construction.
  • Why would you incorporate a gaping hole the size of an ATM in your building shell?

    Based on the envelope area of a 1,900 square foot certified Passive House If built just to building regulations (a leakage rate 10m3/hr/m2) the equivalent size hole in the building once everything has been sealed up would be approximately 440 x 440mm.  Whereas what was achieved on this Passivhaus was a leakage area that is 10 times smaller at just 44 x 44mm To put this leakage area into perspective, if a building was built to the backstop allowable leakage rate for building regulations, you could leave a hole in the wall the size of a typical ATM
  • Should tradespeople know about airtightness?

    Achieving a reasonable level of airtightness is important for the energy efficiency of dwellings and the comfort of occupants. The benefits of improved insulation levels and more energy efficient heating systems are lost if warm air can leak out of a building and cold air can leak in energy, leaking energy is leaking money.
  • U values for Dummies

    In the course of our day to day business, we encounter plenty of customers, builders and trades who find U values a little confusing especially when it comes to understanding what the U value actually means and how it will affect or benefit the performance of a building, so we have compiled a brief 'U-Value for dummies' style explanation to help.

Items 1 to 10 of 11 total

Page:
  1. 1
  2. 2