Energy Efficiency - Why measuring ‘performance in use’ is the key to energy efficiency in buildings

Guest Article from Professor George Martin, Low Impact Building Centre, Coventry University

With approximately 80% of the properties that exist today still being in existence in 2050, the key issue for landlords in the run-up to the 2018 change is that they understand the scale, nature and cost of the various interventions that will be needed to update properties now

Source: www.sustainablecommercialsolutions.co.u

For the past 10 years or more I have been driven by the mantra - If you can’t measure it you can’t manage it. This applies to each and every key performance indicator linked to the built environment sector with energy arguably being the most important. It is for this reason that I consider it essential that the Government mandates the use of Display Energy Certificates (DECs) for all buildings as a vital first step to cutting carbon emissions.

The Display Energy Certificate (DEC) provides an up to date snapshot of how well a particular building is performing, based on actual energy consumption unlike its poor relation the Energy Performance Certificate (EPC) that only provides a theoretical rating based on assumed patterns of use and occupation and can be up to10 years old!  The DEC also reveals what the rating score was in previous years. Consequently it is possible to see at a glance the progress in making that building more energy efficient and less costly to run.  There is now considerable evidence (initially anecdotal, increasingly academic) that requiring energy usage to be professionally monitored and the results made visible, delivers enormous improvements in performance.

Landlords need to be aware that the Energy Act 2011 proposes to make it unlawful to lease residential or commercial buildings with an Energy Performance Certificate (EPC) rating of F or G from April 2018.  In addition, there is a requirement for all new build domestic to be 'zero carbon' from 2016 and for new build non-domestic to be ‘zero carbon’ from 2019.  However, the biggest challenge, especially for landlords, relates in particular to the UK's ageing property stock, not built for a world of high energy prices and carbon reduction targets, and lacking in investment in low carbon retrofit over time.

Source: http://valentemike.blogspot.co.uk

With approximately 80% of the properties that exist today still being in existence in 2050, the key issue for landlords in the run-up to the 2018 change is that they understand the scale, nature and cost of the various interventions that will be needed to update properties now. And that means learning in more detail about how properties actually perform in use.  A one-size-fits-all approach will not work and landlords will need to develop an evidence based approach, backed up with a robust whole life cost database for their properties.  Smart landlords will be using sensors to monitor energy use against temperature and other indicators such as relative humidity in order to identify more specific issues – so that they can identify whether the source of any inefficiencies is due to the building fabric, the equipment, the maintenance regime or indeed the behaviour of occupiers.

Property developers and landlords also need to ensure that their design, delivery and maintenance teams do not have a blinkered approach to energy efficiency and carbon reduction - as it is vitally important to ensure that the health of the fabric and the occupants are also considered. The existing stock of ‘leaky’ properties, whilst bad for energy efficiency, is good in terms of ventilation and here there is some distressing news from recent research that is showing that many - if not most - of the Mechanical Ventilation and Heat Recovery units installed in recent times are underperforming, which is seriously bad news for the occupants.

It is most certainly not right to assume that all 'modern' property will achieve a good performance in use just because it has a good EPC rating or indeed an ‘high’ BREEAM design rating.   Even the highest spec builds with energy efficiency in mind may not be performing as expected. The limited performance gap research available has demonstrated that design targets (and we must remember that EPC is a design tool) are missed by between 20% and an astronomical 500%. We must stop assuming that sustainability-minded design and construction methods are the whole story. Buildings need to be monitored and evaluated for performance once occupied.  Only then is it possible to gain a clear picture of the performance in use and capture the learning for future designs.

The property sector needs to move from making procurement decisions based on design tools (e.g. EPCs), capital cost and payback time to making primary decisions based on the performance in use (DECs)  and 'whole life costs', backed up by an assessment of the return on investment.  

In turn, as attitudes and understanding begins to evolve around performance  in use and whole life costs, the construction industry and here I include clients, designers and constructors, will become more focused on delivering buildings that perform sustainably i.e., environmentally, socially and economically.

Professor George Martin, Low Impact Building Centre, Coventry University

http://www.coventry.ac.uk/business/supporting-your-business/sustainable-building-futures/

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Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog.

Subsidence – Part 2 – Factors that contribute to subsidence and what to look for

As with tree roots, a drainage system is buried therefore not obviously visible at the time of an inspection.  It always amazes me how people tend to ignore the condition of the below ground drainage system when purchasing property and do not seem to see this as important

Source: http://www.users.globalnet.co.uk/

In last week’s article I gave an example of the consequences of building subsidence, which can be extremely disruptive and expensive to deal with, however I also emphasised that the vast majority of subsidence damage is less serious and can be rectified reasonably easily.  I also identified that to the average householder the mere mention of the word subsidence strikes fear and panic into them as there is a perception that subsidence damage is always serious. As you would expect and as I have mentioned many times before, if you are thinking of purchasing a property it is always advisable to have a professional, such as a Building Surveyor, inspect the building before you commit to buy.  The Surveyor’s report will identify any issues that are present and inform you if any are serious.  A Building Surveyor will also highlight factors that may contribute to subsidence in the future and not just focus on the here and now.  There are a number of factors that could lead to subsidence and some examples are discussed below:

Clay Soils

To support a building it is essential that the load bearing capacity of the ground is capable of supporting the dead load of the building (the building’s self weight) as well as any imposed load (furniture, fitting, people, snow etc.), once completed and occupied.  The type of ground is essential to a building’s stability as this will determine the most appropriate as well as the depth of the foundation that should be used.  When siting a building, clay soils are particularly problematic compared to most other types of soil because clay has the ability for significant volumetric change depending on how much water/moisture it contains at any particular time.  When clay is wet it will swell and therefore expand, however when the ground starts to dry out all of this moisture is slowly removed and the clay will shrink.  Think about this process happening with a building on it!  If the ground is constantly expanding and then shrinking, then it is inevitable that the weight of a building will eventually be effected by these changes and cause the building to move.  Having said the above there is no reason why a building cannot be constructed on clay as long as this is established through ground investigations and appropriately catered for in the design.  This may involve deeper foundations, as well as the inclusion of root barriers where trees and vegetation may be in close proximity to the building.

Trees

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Whilst inspecting a property, as well as focussing on the building itself I would always look very closely at the surrounding environment and in particular the size and location of trees.  If not managed, trees and in particularly their roots have the ability to undermine foundations, damage drains and cause significant damage to a building.  The problem with tree roots is that you often cannot see the extent of the root growth or proximity to the building because they are buried.  This however does not mean that they should be ignored and where trees are deemed the pose a threat to a building then the services of a tree expert (Arboriculturist), should be called upon.  This is necessary because different species of tree will exhibit different characteristic in terms of size, growth rate, root spread etc. in addition to advice that can be provided in respect of the condition of trees and any recommended remedial action.

Tree roots do a number of things when in the ground.  Firstly they take up large amounts of water from the ground.  Given what has been discussed above in respect of clay soils you can easily see that in continued spells of warm weather and high temperatures that clay soil and tree roots are not a good combination and together this will significantly increase the potential for subsidence.  Secondly, as the roots grow they have the ability to physically impact on soils, particularly soft/granular types which can undermine stability especially when they have a foundation and a building siting upon them.  Also, as can be seen below tree roots have the ability to damage below ground drainage.

Drainage

Although it is possible to make a broad assessment of a drainage system during an inspection, by lifting manhole/inspection chamber covers this is limited to a small number of access points only and does not identify the condition of the vast majority of the drainage system around a building.  As with tree roots, a drainage system is buried therefore not obviously visible at the time of an inspection.  It always amazes me how people tend to ignore the condition of the below ground drainage system when purchasing property and do not seem to see this as important.  Even if there is no visible indication of any issues with a drainage system it is still worth considering a CCTV inspection of the system is carried out.

Below ground drainage is quite vulnerable and can become damaged in a number of ways.  Ground movement, even subtle movement can result in drains becoming displaced and fractured, particularly around the joints.  Tree roots can also damage below ground drains and find their way into the system.   If this type of damage does occur then the surface and foul water, which is usually heading toward a sewer, will actually start to discharge at the point/s where the drainage is affected.  If left undetected for a period of time then vast amounts of foul and surface water can be discharged into the ground around a building, which over time will start to influence the stability of the soil, and eventually lead to ground movement.  The lesson here is always establish the condition of the below ground drainage system and deal with any problems quickly, before they become much more serious.

Adjacent Excavations

Source: www.thesun.co.uk

A building could sit quite happily for many years on stable ground without any problems and will only be affected if for some reason the ground conditions change.  One way this could happen is works being carried out in close proximity to a building that requires excavations.  If excavations are carried out to a depth and distance that could undermine or influence the stability of another building then this can cause movement, sometimes, sudden movement.  This should be considered in design where it may be necessary to provide temporary support. I have encountered this on numerous occasions where ground movement has been caused by a neighbour excavating (usually foundations) and usually through ignorance has not considered the stability of their neighbours building.

Leaking Rainwater Goods

Even simple repair and maintenance tasks, if left unattended over a period of time can introduce large amounts of water into the ground, which can affect the soil and undermine foundations which can cause ground movement. Rainwater gutter and downpipe repairs are usually inexpensive however this is one of the most common defects that a Surveyor will encounter when carrying out inspection. 

The article above provides a quick overview of some of the factors that could contribute to subsidence.  The points raised are not exhaustive (there are others) and you will note that no attempt has been made to discuss mining subsidence, which is a subject in its own right, perhaps for a future post. 

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Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog.

Subsidence – Part 1 – Not all it’s cracked up to be!

When you see cracking in a building it will not always be, in-fact is very rarely likely to be subsidence.  This can only be established through a comprehensive building survey and detailed investigations

Source: http://www.subsidenceforum.org.uk/

Whilst inspecting buildings I have learned over the years to be very cautious in the terminology I use in the presence of Clients because there are some words that just provoke panic.  Take asbestos for example, or cracking or even subsidence.  These words strike fear into many people mainly as a result of what they have seen on the news or read in the media.  It is fair to say that sometimes these fears can be realised if any of the above examples are found to be present/occurring in a building, however in the vast majority of cases, these issues can be dealt with relatively easily.   This is generally a result of a lack of real understanding, which is why it is always advisable to seek professional advice from a Building Surveyor or Structural Engineer.

When I first graduated from University I joined a Property Consultancy who’s main area of business was dealing with subsidence insurance claims as Loss Adjusters.  My role was to visit site with a more experienced Structural Engineer, who would make an initial assessment, and then I would be required to manage the claim to a conclusion.  This often involved crack monitoring to establish whether any movement was historic (had now stopped) or progressive (was still continuing).  This was a crucial part of the process as it is pointless dealing with the effect of subsidence until movement has been stopped.  On the occasions where movement was found to be progressive, it was often first necessary to undertake substantial remedial work such as underpinning to stabilise the building.  In these instances the whole process could be lengthy and disruptive for the residents and in some instances required temporarily decanting of the occupants to alternative accommodation for the duration of the works.   Most home insurance policies will cover the risk of subsidence and incorporate an excess payment in the region of £1000 (always check the wording of your policy because there can be variations).  This demonstrates that the effects of subsidence can be disruptive and even though it may be covered by home insurance it can still be expensive.

Source: http://www.geoconsult.co.nz/

The above scenario provides an example of what can happen at one end of the scale, however as already stated the vast majority of subsidence claims I managed were dealt with quickly and with minimal disruption, many proving not to be subsidence at all.  When undertaking building surveys, a Surveyor will not just identify where and why subsidence has occurred, but also look for indicators that may contribute to subsidence in the future.  Before providing you with details of what I would look for during a survey (this will be provided in part 2 of the article), I think it is important to first understand exactly what subsidence actually is.

Building design should involved careful consideration of the type/load of the building, the type of foundation used and ground bearing capacity and nature of the ground, the height of the water table and so on.  These types of investigations should help to ensure that once the building is complete and occupied that it does not sink!  Subsidence however is not the same as settlement.  Settlement usually occurs in new or relatively new buildings. As buildings are very heavy they cause the ground to compact, although this will usually stop after a short period of time.  Also, most buildings are constructed in a variety of materials, all of which need to settle and have different rates of shrinkage.  Subsidence occurs when for some reason the load bearing capacity of the ground that a building is placed upon is no longer capable of accommodating that load.  The reasons for the change is the load bearing capacity can occur for many different reasons and many years after the building was first completed.  It is quite feasible for a building to sit quite happily on a piece of ground for many years and due to some of the influences discussed it part 2 of this article, it can start to move.

Cracking in buildings occurs for many different reasons so it is fundamentally important that anyone who undertakes inspections or gives advice in respect of cracking should not make rash judgements and should gather all of the evidence before arriving at a possible cause.  In order to aid the inspector, which as stated previously, can be a Building Surveyor or Structural Engineer, it might be necessary to recommend other investigations such as geo-technical surveys to establish ground type, composition, contaminants etc., trial holes to establish foundation depths, CCTV inspection of the drainage system and possibly an arboricultural survey to give advice on any trees that may be an influencing factor.  The choice of which investigations are needed will be decided once the inspector has made an initial assessment of the cracking.  Therefore when you see cracking in a building it will not always be, in-fact is very rarely likely to be subsidence.  This can only be established through a comprehensive building survey and detailed investigations.

In part 2 of this article (next week) I will discuss subsidence in more detail and provide information in respect of the things a Building Surveyor will look at to identify when and how subsidence is occurring and indicators that may suggest that subsidence can occur in the future.

Please feel free to share this article and other articles on this site with friends, family and colleagues who you think would be interested

Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog.

Affordable Housing - What does affordable actually mean?

For the Government to set targets for ‘affordable housing’ is actually misleading because affordability is relative to the state of the housing market (both sale and rental sectors) at any particular moment in time. 

Source: http://www.myfinancialtips.com/

As my children were growing up I was carefully watching the housing market with dismay as house prices through the mid-nineties and into the early part of the millennium continued to soar.  I am sure many parents have the same concerns and now wonder how on earth their offspring will manage to get their feet onto the property ladder.  In 1986 my wife and I purchased our first house.  A three bedroomed mid-terraced property (a previous right to buy property on a council estate) with a small front garden and a good size rear garden, perfect for raising a young family.  The house cost us £19,000 for which we obtained a mortgage very easily at the time.  Prior to putting in our offer, I remember having a number of sleepless nights wondering whether we could afford the property as it was actually £1000 above our maximum budget. 

Nowadays with the accelerated rise in house prices since then, things have changed and the decisions facing those who want to enter the property market for the first time have multiplied significantly.  Decisions whether to save for a larger deposit will often result in either ‘living with the parents’ longer, or possibly renting.  The problem with renting of course is that rental values have also risen quickly, which results in money which could be saved for a deposit being used for monthly rent payments instead.  It’s a vicious circle and one that is not likely to change as property prices will never return to the levels I discuss above, when I purchased my first home in 1986.  My son who is now 23 years old keeps telling me (tongue in cheek I hope!) that he is patient and is more than prepared to wait for my wife and I to fall off our perch and take the inheritance! I tell him that even in this circumstance the Government will swoop down and take a large chunk through inheritance tax, which he is not best impressed with at all!  The above demonstrates the difference with how I perceived ‘affordability’ less than 30 years ago and how the new generation of first time buyers will perceive what is affordable for them.

  

Property Rented Sector

The UK Government definition of affordable housing is:  ‘Affordable housing includes social rented and intermediate housing, provided to specified eligible households whose needs are not met by the market. It can be a new-build property or a private sector property that has been purchased for use as an affordable home’.  (Intermediate housing is housing which is often provided on a fixed term basis by a Registered Social Landlord where rents are set in-between the Social Housing Rent and Open Market Rent)  On 14 July 2011, the Minister for Housing made a written ministerial statement announcing the outcome of the affordable homes programme 2011 to 2015, managed by the Homes and Communities Agency.‘As part of the programme, we introduced the affordable rent product. This allows registered housing providers to charge no more than 80% of local market rent (including service charges where applicable) for new affordable homes’. Source: www.gov.uk.

Source: http://blog.windhillrealty.com/

It appears therefore that ‘affordable’ rent is deemed to be 80% of the local market rent? If this is the case then affordable rent will continue to increase parallel to any increase in local market rent.  This again demonstrates the confused perception of what ‘affordable’ actually means.  The Government can regulate the Social Housing Sector, but what about those in private rented accommodation. In a recent article in the Guardian (Link), Hannah Fearn discussed the UK private rented sector and concluded that large parts of the UK are now unaffordable for low and middle income households:

‘Unlike the previous two generations, a large proportion of our population is facing life in unstable, often unfit and largely unaffordable housing with no prospect of either transitioning to secure social rent or stepping into home ownership in sight.

Home Truths, a report from the Resolution Foundation published on Monday, revealed that for low- and middle-income households in the private rented sector whole swathes of the country have become unaffordable. Using data supplied by Hometrack, the thinktank calculated that a third of the country was now off limits to poorer private renters at a time when half of young low- and middle-income households are living in this tenure.

For a renting family with a combined income of £19,000 a year, half of the country is now unaffordable because the cost of accommodation takes up more than 35% of monthly take home pay’

Until we address the problem of housing supply in the UK then it will be impossible to avoid natural economic market conditions driving the market in an upward direction.  Where we have high demand and limited supply then the only outcome will be a continuing increase in rental values. 

Property Purchase Sector

When the Government emphasise the need to build affordable housing what do they actually mean for those who want to purchase a house for the first time?  Well again, this is not clearly defined and there is no threshold of ‘affordable’ in terms of property value.  The main way in which the Government attempt to make houses affordable is to offer numerous support schemes, initiatives, incentives, etc. These include the recently introduced help to buy scheme, shared ownership, shared equity (such as first buy), and so on.  Most of these schemes offer a percentage incentive, whether that is in shared equity or a low interest, government guaranteed loan, based upon the value of the property.  While these schemes may help first time buyer onto the property ladder what is really needed, as with the rented sector discussed above, is an increase in supply of new build houses and quickly!  

A recent article in the Guardian (Link) emphasises the impact of the lack of new housing in the UK: ‘Two numbers sum up one of the biggest problems in Britain today. They are: 240,000 and 108,190. The first – 240,000 – is the rough forecast for how many new homes are needed each year to meet demand; while108,190 is the actual number of new homes added in England in the last financial year. That shortfall swells and falls, but is always there – and it accounts for the country's housing crisis’. At the risk of repeating myself, until we address the problem of housing supply in the UK then it will be impossible to avoid natural economic market conditions driving the market up.  Where we have high demand and limited supply then the only outcome will be a continuing increase in house prices. 

So to answer the question of how to define ‘affordable’ is actually missing the point.  For the Government to set targets for ‘affordable housing’ is actually misleading because affordability is relative to the state of the housing market (both sale and rental sectors) at any particular moment in time.  Affordability is a moving feast and will never be a fixed entity due to the complex nature of the World we live in.  One thing that is for sure is that over the last thirty years due to the significant increase in house prices as well as the increasing demand for a limited housing supply in the UK, is that the threshold of affordability has changed.  The current generation of first time buyers face much higher house prices and rents which will continue until something is done to significantly increase the supply of new houses.

Please feel free to share this article and other articles on this site with friends, family and colleagues who you think would be interested

Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog.