Category Archives: Building Regulations

Are solid walls making a comeback?

House construction techniques have developed from historic solid wall methods.   Go back over 200 years and solid walls were made from local stone inner and outer faces with rubble, stone and earth between forming a dense and thick mass that held itself together.   Due to its thickness rain rarely penetrated the width of the wall.   Air tightness did not exist, in fact the walls were naturally breathable.   Thermal properties worked differently from today’s high insulation techniques aided by the thickness of the wall and the fact that the inner stone would have been warmed internally by open fires.

As bricks were developed in the 19th century the ability to build thinner walls, affording more internal floor area, became apparent.   Taller buildings used the method of thickening the masonry at lower levels and thinning out as floors rose.   Typically, a three storey brick built solid wall construction might see ground floor thicknesses at three bricks thick, first floor at two bricks and single skin for the top floor.   This method helped reduce weight as the building went up.

Thinner walls began to see rain penetrate to the inner face presenting all sorts of problems.   Thus, the cavity wall was born; using two separate skins of brickwork, the outer skin kept the rain out and being separated from the inner skin prevented transition of moisture to the inner skin.   Later, insulation was added to the cavity, an ideal place to locate and protect a soft product, to improve thermal performance.   So today, with relatively high performing insulation products, the understanding of how air tightness improves thermal performance* and other efficiencies in material fabrication, today’s cavity wall is a high performer.

So, why go back to solid wall, even with modern insulation products?   Where is the benefit over cavity wall techniques?

Wall thickness can be one benefit.   With insulation demand increasing, cavity walls are getting thicker, often over 300mm to meet today’s requirements.   A solid wall method, using single skin masonry (100mm), can be less than 300mm including rain screen cladding.   Placing the insulation on the outside enables the inner skin of masonry to act as a thermal mass, much like historic methods achieved, reducing the output of heating systems.   Thicker inner skins, perhaps using block laid flat (215mm), will improve thermal mass.

Remember, in a cavity wall, the outer skin of brickwork is not load bearing.   It is merely a rainscreen intended to keep the weather out.   Therefore, by replacing what is a relatively expensive product to buy and high labour intensity to build with something cheaper, sustainable and thinner whilst maintaining the inner masonry load bearing wall and, then outer insulation layer results in a modern solid wall construction.

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5 easy ‘green’ improvements you can add to your house.

green jumper

Everyone knows about turning lights off when you’re not in the room and not leaving your TV on standby when it comes to ways of reducing energy usage in the home. I’m not going to tell you about these things or that energy efficient bulbs really do reduce your electricity usage.

Here I have 5 simple things that you can physically do to your home, yourself or through a trained professional, without needing Planning Permission. I cannot exclude any requirement for Building Regulations as technically approval is required to upgrade thermal elements on your house, bizarrely.

For now, here are 5 great investments you can make to your home that will reduce heating demand and make your home more efficient and ‘green’:

1. Cavity Insulation: if you have a masonry cavity wall constructed house that was built in the 20th century (that’s around 15 years ago or more) chances are there is no insulation in that cavity. Having some blown insulation injected into your wall will help keep the heat you produce in your home. Other forms of construction will need a different solution and wrapping your home with insulation on the outside would be a great way to go, however this may require planning approval if you use a different finish material than the original house (i.e. Render in lieu of brick) and that’s a whole other blog.

2. Loft Insulation: this is fairly easy and cheap to do yourself. Assuming you have an empty loft, the ideal method would be to place one layer of mineral wool quilt insulation down between the ceiling ties followed by another layer over the top. A little added benefit would be to lay the top layer perpendicularly as this will cover the gaps in the layer below where the ceiling ties are. Remember not to squash this type of insulation as it works best when inflated. Keep this insulation away from the roofing felt too (the black stuff between the rafters and tiles) otherwise you may block ventilation paths for fresh air that come through the eaves. This ventilation stops your rafters rotting when condensation forms as it will evaporate that moisture.

3. Window and/or Door Upgrade: even if you already have double glazing, replacing them with new is likely to make a noticeable improvement. The older your current windows the bigger the improvement. Some glazing companies will even recycle your old uPVC frames and glass too giving you a greater sense of well being towards the environment. Your windows and doors are the weakest thermal element of your house so investing in them will be worth the money. If you really want to improve them, go for triple glazing as this can make them as effective as your walls or roof, or pretty close at least.

4. Solar Thermal: this is a method of providing hot water in your home thanks to that big bright yellow thing we see in the sky from time to time. What’s great about solar thermals in the UK is that they will work even when it’s cloudy. Here’s the science; it’s something about the ultraviolet light passing through clouds, which is the bit that heats the system. Just a couple of panels on your roof and a hot water tank inside and you’re done – your boiler no longer needs to heat water.

5. Wear a Jumper: turning your thermostat down just one degree will reduce your heating demand and what’s more, you’re not likely to notice one degree all that much. If you have zone controls for your heating (or even a simple TRV on your radiators) you might think about turning areas or rooms off when not in use too. If you do feel a chill, wear a jumper – it’s insulation around you to keep your heat in!

Nearly all of the above ideas can be supported by local authority grants and it is worth a quick internet search to find out what is available, though I am not sure many people give jumpers away for free. Another good place to ask will be your energy provider who may have a grant or offer available.

If you have a listed building it is worth checking with your local authority conservation officer before committing to any of these, other than wearing a jumper, as they may be detrimental or even damage the protected fabric of the building.

Holding on to the heat you produce in your home will not only reduce your energy usage and therefore save you money, it will be better for the environment too.

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Do I need Planning and is Building Regulations the same thing?

Believe it or not, I get asked this very question every once in a while. To those in the know the answer is simple but for those that are embarking on their first development it can be confusing.

In a nut shell; these are two different departments with two different applications each requiring different information. Chances are you will need them both.

Sometimes your development will fit into what is called Permitted Development, which is a whole other blog. This is when planning permission is not required. And if this is the case you can skip to the second part of the question; building regulations.

Building regulations is often inevitable. This is a set of minimum standards developed by the government to ensure buildings are safe, warm and suitable for all, plus a few environmental things thrown in to boot. With the right details and specifications, this statutory application process is always approved.

Planning permission, on the other hand, is a consideration of the development in relation to its surroundings and setting. Here appearance matters rather than construction method. Sometimes this application can be refused for reasons that sometimes do not seem fair.

Both applications can be submitted by individuals, lay people if you will, or they can be supported and delivered by an agent; an architect, perhaps. The benefit of using an agent is their experience and education on each subject. An architect can certainly bring value to a project in this regard with sound advice and strong justification.

So, if in doubt about planning or building regulations, the best thing to do is speak to an architect. Not only could they procure both applications on for you, they may even make the process easier and much less stressful for you.

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5 good reasons to employ an architect

Why would you employ an architect?
An architect is a building designer. They train for 7 years (as much as a doctor) to understand design within the built environment. They are skilled in many areas including; building design, planning policy, building regulations, building contracts and construction law to name a few. With such a high skill base why would you employ any other professional to design your building? Here are five very good reasons to employ an architect on your next building project:

1. Creativity. An architect sees opportunities that can improve your property both financially and through quality of space. They are problem solvers, trained to find solutions. Architects look at the bigger picture and design space specifically to your needs.

2. An architect can handle the paperwork on your behalf to save you having to negotiate the planning maze or try to understand the building regulations. They can also advise you on any other professionals you may need for your project.

3. Architects are trained professionals governed by a code of conduct. Every architect is registered with the ARB (architects registration board). Some are also members of the RIBA (Royal Institute of British Architects). Both organisations have a code of conduct for members to abide by. These codes are created to protect you as the customer and ensure you get the highest quality service from your architect.

4. Architects can support you while your project is being built. They can act on your behalf with great construction knowledge to ensure quality is being delivered by the builder too. They can provide routine valuation certificates (sometimes with the aid of a Quantity Surveyor) to ensure you are not over paying for the work completed on site.

5. An architect will consider the design quality of a space through a number of factors; how the space is intended to be used, site constraints, planning policy, best construction practice, what materials would be best to use and how to control costs.

Bizzy Blue Design Ltd is an RIBA Chartered Architects practice. It provides the highest level of design and architect’s services to its clients. Working primarily in the residential sector they also support commercial projects and historic & listed buildings. The personal one to one service brings a tailored service to each individual client maximising the potential of their project.

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What changes are in store for the April 2014 Part L Document?

HCD group – Changes to the Building Regulations Approved Document Part L

Scheduled for April 2014

 

What changes are in store for the revised Part L documents this April?

In an effort for the government to demonstrate a reduction in carbon emissions for the United Kingdom the new revision for Part L of the Building Regulations will be released in April 2014.   These changes are intended to make a step towards a potential zero carbon new build house in 2016 and extensions in 2020.   Generally speaking, the changes are targeting a reduction of 6% in CO2 emissions for new build houses and 9% in non-domestic buildings this time around.

This modest increase in thermal properties, rather than the projected more significant step, is a deliberate act by the government to easy the change on the economy.   Their figures suggest that these changes would result in a 1.2% construction cost increase.   Reality suggests that the increase is more likely to be significantly higher at around 8-10%, which will actually be quite a hit on the construction economy.

 

So what are the changes and how will they impact on design?

For new build houses all of the external fabric elements have had their U-values improved.   Typically, walls will be 0.18 W/m2K, floors & roofs will both be 0.13 W/m2K and windows/doors/rooflights 1.4 W/m2K.   Limiting standards, the lowest any element can be, remain the same as current levels.   One point is clear with the revised figures is that a specification will pass if within the typical U-value targets and the updated 2012 SAP (Standard Assessment Procedure) calculation system will also pass at these levels, which was not always the case.

The revised Part L bases its standard pass rate without the use of renewable energy though, allowing any introduction to be an improvement on the basic provision against carbon emission reduction.   Compensation against reduced U-values can be tackled with the introduction of renewables, for example.

Party walls have been reviewed after evidence was found to support the argument that they act like chimneys drawing warm air from the spaces out through the roof.   As a result U-values have been applied here too with an option to provide a solid wall with block laid flat construction, though this method is likely to require attention to combat noise transfer.   A full filled insulated cavity party wall is the best solution providing it is sealed at all exposed edges.

Fuel factors are a new element within the overall assessment.   This set of figures provides a pre-determined factor against which type of energy is being used within the building.   Gas is the preferred and best option while electricity gets hit the hardest.   Be careful when installing heat pumps that require grid electricity to run them.

Efficiency of installed equipment, such as fan system for heat exchangers in passive houses and all lighting units, have been improved.   This will have an impact on fan systems in particular with manufacturers needing to improve the efficiency of their products to avoid duct sizes increasing.

These principles are the same for extensions to existing dwellings, though the required U-values are not as low as new build.

Again, U-values to external elements have been improved for new non-domestic buildings but the most notable change is the reduction in air permeability.   This means that connection details and then the construction of those details needs to be carried out with more attention in order to achieve the requirements.   As with housing, renewable energy is not included in the basic specification level allowing these to be added as an improvement or as part of a compensation for reducing performance of other elements.

Both for domestic and non-domestic new builds a report has to be provided that demonstrates a consideration of high efficiency alternative systems, such as renewables, district heating or heat pumps perhaps.   A simple statement is required to explain why more efficient systems have not been employed but there is no method to enforce or challenge the report.

Extensions to non-domestic buildings have retained the current requirements for U-values.   However, renovation of existing thermal elements will now require consideration at building regulations and will have to meet the current standards.

In summary, there are general improvements to all external elements in terms of thermal efficiency that targets a reduction in CO2 emissions by 6% for domestic buildings and 9% for non-domestic and a new SAP calculation for domestic buildings; the 2012 system.   These all come as a stepping stone towards a projected ‘zero’ carbon level for both domestic and non-domestic by 2020.   Watch this space for the next set of changes in two years time, we might have only just got used to these changes by then.

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