Bosch Thermotechnology Variable Refrigerant Flow Systems (VRF or VRV)

In what can only be described as a very turbulent year, many businesses have had to shut their doors and have all but forgotten about the general upkeep of their sites. With priorities shifted to keeping companies afloat and staff employed, maintenance and servicing has taken a backseat, and many systems will be deteriorating unnoticed. It goes without saying that one of the first tasks that employers will have to tackle when returning to work is a deep clean. As we are still in the throes of a pandemic, a clean and disinfected workplace is the number one priority that needs to be ensured, before any staff can be welcomed back to work. This should be closely followed by maintenance of the site’s equipment. Importance of regular HVAC maintenance Regular HVAC maintenance is extremely important as it keeps systems performing efficiently and effectively Regular HVAC maintenance is extremely important as it keeps systems performing efficiently and effectively. The nature of HVAC maintenance does change depending on the time of year, and with some sites being shut for months and through different seasons, managers will need to review their current equipment to ensure it is compliant and working correctly as soon as possible as signs of normality start returning and facilities begin to reopen. While warehouses and factories may have still been operating in some capacity over the last 12 months, many office buildings have seen little to no employees for more than a year in some cases, therefore, risking deterioration and even damage to their systems going unnoticed and untreated. But with so many pieces of equipment at each site, it is often hard to know where to start and what to prioritize. Following HVAC manufacturer’s recommendations In order for businesses to keep functioning as best as they can and to avoid any more disruption, those in charge of maintenance and servicing need to be educated on how the conditions of a system affects the type of work it needs. Manufacturer’s recommendations should also be taken into account. To help define what these are and how to approach them, mechanical and electrical engineers recommend: The coils and pipes in HVAC equipment that are responsible for heat transfer are checked regularly, because if the equipment gets dirty, it won’t transfer heat and energy as well. Checking controls annually to ensure that the HVAC system is running properly, as control calibration can alter. By scheduling regular check-ups, accurate operation is maintained. Maintaining equipment with fans quarterly to maximize longevity. Three key areas include monitoring the impellers, belts and bearings for any dirt, wear and tear, friction or erosion. Keeping an eye on filters, as when they are clogged, it increases the pressure drop in a system, which makes fans work harder to maintain the same airflow. A quarterly clean is usually sufficient for most filters. This is also true of strainers in systems. Optimizing HVAC and electrical equipment With spring now upon us, businesses need to optimize their HVAC and electrical equipment for maximum efficiency With spring now upon us, businesses need to optimize their HVAC and electrical equipment for maximum efficiency. This includes reviewing the sequence of operations for a morning warm up and cool down. However, it’s important to remember that because of prolonged closures over the last 12 months, autumn and winter checks, and in some cases, even summer checks were not able to be carried out in 2020, so before the spring work begins, backdating the maintenance is a good place to start. Ensuring buildings’ energy efficiency With the help of experts, HVAC maintenance doesn’t have to be time-consuming and overwhelming, but it’s a critical part of maintaining an energy-efficient building that is both comfortable and reliable. With regular servicing and some basic knowledge of what is required, sites can maintain optimum efficiency all year round. Noise complaints can also be an issue, if HVAC maintenance isn’t carried out regularly. Spring is a good time for businesses to perform services on their equipment, prior to the summer months starting and should be used to ensure that condenser coils and air handler filters are both clean. The dirtier the equipment, the noisier and less efficient it becomes, which is bad news for any business. Preparing buildings for staff returning to work When a building is returning to normal occupancy after a lengthy closure, additional checks must be considered before reopening is discussed. When a building is initially mothballed, it must be prepared for long term vacancy, but many businesses will not have had this opportunity before the national lockdown, which basically entails that these checks will not have been carried out. After a building becomes unoccupied, it is not the case that maintenance activity should also stop After a building becomes unoccupied, it is not the case that maintenance activity should also stop. At the very least, the frequency of existing planned maintenance will change, but in some cases, more maintenance tasks are required in order to keep the site ticking over. This includes flushing of water systems, Legionella testing and insurance inspections to keep the property functional and compliant. Countering health and safety issues  As the COVID-19 lockdown restrictions are lifted across the United Kingdom and many businesses are gradually reopening, it will present health and safety problems that have not been faced before and will very likely see a surge in services and maintenance being required. With this in mind, it is vital that maintenance becomes a priority as normal service is resumed to not only ensure efficiency, but also to make sure that no employee or visitor to a site is put in danger. Emerging from a surreal 12 months, there is no doubt that companies will still face challenges, so it is crucial that avoidable maintenance problems do not become one of them, so don’t delay in booking routine checks.  

How grooved solutions have been making contractors and engineers reimagine the way they construct risers in vertical buildings? Enter into the right pub, or head to a city’s museum or town hall, and you can often find a picture of how the surrounding area used to look. An image from twenty years ago and the difference isn’t too vast. Fifty years back and there’s a definite change. A picture from over a hundred years ago and it’s practically unrecognizable. And what’s the common theme running through these images? Cities are getting taller. As more people migrated to urban areas, developers saw the need to go higher. But with this comes its own unique set of challenges. How can the safety of ground floor be transferred to, in the most extreme case, level 163? Grooved mechanical pipe joining solutions When it comes to high-rise buildings, there are a number of potential challenges for a piping engineer To find out how grooved mechanical pipe joining solutions are helping developers & engineers go higher, we spoke to Matthew Strohm, Director of Product Development (Piping System Design) at Victaulic. When it comes to high-rise buildings, there are a number of potential challenges that a piping engineer will need to take into consideration, most of which relate to thermal movement and the resulting forces on the building. Other issues such as seismic activity and building creep (the natural movement of a building due to settlement) also need to be taken into account. Compensating for thermal expansion and contraction Specifically related to piping systems and subsequently, pipe joining solutions, is the unique problem of having to compensate for thermal expansion and contraction, while at the same time, accommodating for higher pressure. Change in pipe diameter is not an uncommon concern for engineers, however, providing a solution which could operate at a pressure gauge of 25 bars, or the fluctuating temperature of water, presents its own challenges. It’s with these issues in mind that engineers choose their joining solutions, which is why these are the very criteria we set our Victaulic pipe joining solutions against. Grooved vs. Traditional Pipe Joining For decades, the traditional solutions for joining pipes have been welding, threading or flanging. These are good solutions to choose from, but there is a distinct lack of flexibility in a solution that fuses or flanges system components together. This is where flexible grooved couplings come in. They are solutions that allow controlled linear and angular movement at each joint to accommodate not only for thermal expansion and contraction, but also building sway and creep. So how do flexible grooved couplings manage this? It’s essentially down to the design of their components. The dimensions of the pipe coupling housing key is narrower than the pipe groove, allowing room for movement. Furthermore, the width of the pipe coupling housing allows for pipe end separation, which in turn allows the grooved pipe joint to accommodate movement. Benefits of Grooved couplings There are many benefits of grooved couplings, with space-saving being a key advantage on projects, both large and small There are many benefits of grooved couplings, with space-saving being a key advantage on projects, both large and small. As many project managers and engineers know, saving on space can be the key to unlocking extra value above initial planning. Additionally, grooved couplings are perfectly placed to accommodate for piping movement, whereas welded joints that in their very nature are designed to be fixed in place, need to have an area of space to allow for a welded expansion loop or alternatively, enough space to allow the star-pattern tightening of a flanged flex connector. Saving time, money and labor Besides the savings on space, grooved connections offer contractors savings in three key areas: time, money and labor. The installation-ready design of Victaulic’s grooved couplings allow for an easier installation, meaning a process which might take 30 minutes through a welded solution for instance, can now take just five minutes. As any contractor will testify to, this is valuable time that can be used for other parts of the project. With a reduction in time comes savings in cost and labor. Naturally, less labor is used for the same job and in the case of grooved couplings, less skilled labor is required (in comparison to the high skill level needed for welded joints). It’s these aspects that will ultimately deliver contractors with valuable project savings. Grooved connections offer savings in three key areas: time, money and labor Mechanical riser solutions There are 3 ways to accommodate for thermal movement within risers using a grooved mechanical system: The first method is called top of riser free-floating method and involves installing rigid couplings on the riser and two flexible couplings on the horizontal adjacent piping at the top of the riser, which can reduce the need for riser clamps or other structural during installation and allows the system to move freely within the design tolerances. The second method involves working with grooved expansion loops that help to save up as much as 2/3rd of the size of welded U-shaped expansion loops and avoids forced welded pipe deflection. While welded expansion loops require eight welded joints to assemble, the forces exerted on the joint are far greater than those applied on a grooved expansion loop, and generate greater stress, which ultimately requires larger anchors and guides in order to direct the movement. The third method is working with grooved expansion joints instead of traditional in-line expansion joints, which typically have wear parts and manufacturer-recommended maintenance cycles of five years, which also poses problems due to riser accessibility once the construction is complete. Grooved expansion joints like the Victaulic Style 155 are maintenance-free for the life of the system. Importance of anchors In a system using only flexible joints, risers are installed with anchors at the top and bottom and the piping guided every other length to prevent angular deflection at the joints within the piping run. Anchors distribute the movement forces across the structure and also provide the important task of directing pipe movement. At the pipe anchor location, there will be no differential movement between the piping and the building structure, which forces the pipe to thermally expand or contract from that location. This allows the design engineer to control how and where the movement in a system occurs and to provide the best solution to accommodate that movement. A10 Grooved Riser Anchors upgraded A good manufacturer will always listen to customer demand, especially in an evolving market A good manufacturer will always listen to customer demand, especially in an evolving market. Off the back of strong feedback from contractors, Victaulic recently upgraded its A10 Grooved Riser Anchors to a standard product. With the primary functions of carrying the weights and forces that act downward to the base of the riser and connecting the riser to the rest of the structure, the anchor has been providing sturdy support for some of the tallest buildings around the world. Future trends for high-rise buildings One trend already taking place, and I expect to continue, is contractors bringing riser experts into the project at an earlier stage. It just seems to make logistical sense to operate in this fashion. it’s a more efficient use of time to collaborate early in the process. I believe contractors and engineers will seek assistance from companies such as us to help design blueprints together, working in tandem to produce the right solution. Vertical buildings are on the rise. For generations, people have been moving to urban areas, putting greater demand on housing residents and employees. Through the use of grooved coupling solutions as an alternative to traditional methods, contractors can benefit from greater flexibility, reliability, ease of installation and ultimately and most importantly, speed of the installation process.

The modern technological world is filled with ‘extrusions’. They are all around us, in the form of small and not-so-small cross sections. The function of an extrusion is to form seals between components of complex machinery and keep them functional. And, depending on the ‘type’ used, they can make a big difference to how a machine operates. Some of the most desirable types of extrusion — and especially for use in HVAC systems — are those made from silicone. Silicone, which is a type of rubber, has a robust set of properties. For one, silicone can withstand extreme temperatures, both high and low. Semi-Exterior environments Ranging from -60°C to temperatures exceeding 200°C. (And there are even higher grades that can be manufactured to withstand temperatures well above 200°C.) Ideal for HVAC units that work round the clock to keep large numbers of people in large buildings comfortable in summer and winter conditions. In addition to this, silicone is also one of the more resistant properties to the constant vibrations of working machinery. It can be difficult to locate the source of the problem if a tiny extrusion has dislodged. Vibration-resistant properties make silicone extrusions less likely to disengage or fall out of place, therefore minimizing the need for costly repairs. Finally, silicone is also more durable than most other materials when it comes to exterior or semi-exterior environments, such as that of rain or ultraviolet light. Protecting electrical components Silicone is useful in HVAC systems because it offers enhanced sealing and compression protections As a result of this favorability, there is already a considerable number of different types of silicone extrusions that can be found in a lot of HVAC systems. These include HVAC sealing gaskets, hatch seals and vibration isolation pads. But also silicone sponges, which act as a protective layer of thermal insulation. As well as providing thermal insulation, silicone sponges can double-up as a form of acoustic insulation, with considerable noise reduction and anti-squeal properties. Silicone enclosure gaskets protect electrical components, and environmental seals — as the name suggests — help to keep everything protected from the sometimes harsh elements of the environment outside. Silicone is useful in HVAC systems because it offers enhanced sealing and compression protections over most other materials. Closed cell structure On a material level, silicone has a ‘closed cell structure’, which helps to keep out moisture ingress, along with water and dust. The combination of a closed cell structure, along with sealing and compression benefits, makes silicone ideal for exterior seals and gaskets in and around HVAC systems. The softer grades of Silicone have an excellent memory and low stress relaxation, which in turn helps to prevent common faults with HVAC systems — usually caused by gasket failures made from other materials that soften and compress inaccurately. The low stress relaxation properties require minimal force on behalf of the engineers sealing the enclosures, while the memory-properties of the silicone allow it to conform to awkward shapes and gaps of various widths. Manufacturing HVAC systems proactively with silicone in mind can allow more design flexibility on behalf of the engineers. Inevitable rapid movements General purpose solid silicone or silicone sponge is suitable for many HVAC applications And, as mentioned above, vibration isolation pads work as dampers to protect against the inevitable rapid movements of the systems as they power along. But also to help withstand the vibrations of HVAC units on transport systems, such as buses and trains, which naturally vibrate as they run over imperfections on rail and road tracks. As it happens, general purpose solid silicone or silicone sponge is suitable for many HVAC applications, not just those discussed above. The designs of the extrusions would be different, reflective of their function, but the material would be the same. In some instances, customers may also require a flame retardant silicone — certified to UL94 specifications — in order to meet safety standards in certain situations or environments. Great temperature ranges For all its material advantages, silicone is generally more expensive than the other types of material rubber that are used to manufacture extrusions, such as ethylene propylene diene monomer (EPDM). And while other materials do of course have stand-out benefits of their own — EPDM for example is more hard-wearing than silicone — silicone is still often the extrusion ‘type’ of choice because of its ability to withstand great temperature ranges. This is very important for heating and air conditioning systems. Because some of the most common factors that cause HVAC systems to break down are as a result of seal and gasket failure, which can come about as a result of an overheating unit. Very cold environment Chances of a unit overheating can be just as likely — in fact perhaps more so — where the system has to operate in a very cold environment. With the threat of climate change etched more than ever into the public discussion, we can predict that there will be a steady increase in the amount that this material is used to make up the HVAC seals. And not just because, as temperatures continue to increase and summers get hotter and more prolonged, there will be an increased demand for them. Effective public relations It is no secret that HVAC systems can be relatively expensive to run It will become a matter of effective public relations for managers, building regulators and transport officers to make sure that the equipment they are using — and making — is ‘green’. By using the right materials that help conserve energy and increase efficiency, this will not only sit right with the general public, it should also be more economical, too. It is no secret that HVAC systems can be relatively expensive to run. Minimizing wastage, and the time spent on call outs and repairs will make a notable difference. Of course there are many other ways to also set about making air conditioning and heating units more efficient. Using seals or gaskets made from silicone is just one small piece of the puzzle. But utilizing them will almost certainly be more beneficial than you might imagine. And anything that is a step in the right direction is a welcome change.

Sustainability and environmental impact are core issues of the HVAC market in 2020 or any year. During the last year, HVACinformed.com has addressed multiple facets of sustainability in some of our most popular articles. This retrospective will highlight some of the sustainability articles published during 2020 at HVACInformed.com. An HVACInformed.com Expert Panel Roundtable commented on various aspects of sustainability, including the responsibility of HVAC manufacturers to develop more sustainable, energy-efficient products that can reduce a building’s reliance on fossil fuels. Energy consumption pattern Honeywell has launched a platform that incorporates newer technology. Combining self-learning algorithms with building automation, Honeywell Forge Energy Optimization is a cloud-based system that analyzes a building’s energy consumption pattern and adjusts its settings. Heat networks, or district heating, are becoming an ever-greater part of the industry’s involvement Pete Mills of Bosch Commercial & Industrial outlines how cities are using ‘heat networks’ to achieve carbon emission targets in the United Kingdom. Heat networks, or district heating, are becoming an ever-greater part of the industry’s involvement in larger-scale schemes. The ability to help the decarbonization of heat both now and in the future has made them an attractive solution to the new-build sector, as well as those undergoing deep renovation works. Centralized heat generator Generally, heat networks are defined as a system of supply pipes with a centralized heat generator (Energy Center) that serves multiple domestic or non-domestic dwellings. These are usually in different buildings, but sometimes within a single large building like an apartment block or a university campus. Some U.S. cities are taking the lead to make building performance standards mandatory, thus providing additional incentive for customers to invest in new, more efficient and climate-friendly HVAC technologies. New York City has deployed its Carbon Mobilization Act, which will cut six million tons of CO2 annually by 2020. Washington D.C. adopted the first Building Energy Performance Standard, which will reduce energy use in buildings by more than 20%, thereby lowering carbon dioxide emissions by a million tons annually. Improving environmental performance Newer buildings tend to be designed to be ‘green’, but what about older existing buildings, which still represent the largest share of environmental impact? There is more work to be done in the retrofit sector; and improving environmental performance of older buildings often involves ‘deep retrofits’ that are costly and impact multiple factors inside a building. In the COVID-19 era, there is also growing concern about needs such as circulating outside air, increasing humidity, and improving filtration systems even as older buildings seek to become greener. The consistent theme is a need to work toward better-designed, more energy efficient and healthier buildings The consistent theme is a need to work toward better-designed, more energy efficient and healthier buildings. The California Air Resources Board (CARB) is moving forward with rulemaking that sets limits and deadlines to decrease the use of refrigerants with global warming potential (GWP) in the commercial refrigeration market and in the residential and commercial stationary air conditioning equipment markets. Air conditioning systems California regulations are widely expected to influence the direction of other states seeking to regulate GWP of refrigerants. The addition of biodiesel lowers the carbon content (and thus the environmental impact) of heating oil. The U.S. Environmental Protection Agency says biodiesel reduces greenhouse gas emissions, including nitrogen oxide. The process of making biodiesel from renewable and organic sources also boosts the environmental profile. The Wyss Institute at Harvard University has developed an evaporative cooling system that uses a specially coated ceramic to cool air without adding humidity. Researchers say the approach can yield more affordable and environmentally friendly air conditioning systems for the future.

Pete Mills, Commercial Technical Operations Manager at Bosch Commercial & Industrial outlines how cities are using heat networks to achieve UK carbon emission targets. Heat networks, or district heating, are becoming an ever-greater part of our industry’s involvement in larger scale schemes. The ability to help the decarbonization of heat both now and in the future has made them an attractive solution to the new-build sector, as well as those undergoing deep renovation works. Net zero 2050 The UK’s net zero 2050 target may seem like a long way off. But steps need to be made now in order to reach this, something that our leading cities have recognized. Many have set their own carbon targets to ensure they stay on track. This is why heat networks’ ability to provide efficient heat and hot water to multiple buildings (and as the name suggests, whole districts) is a particular reason why many cities up and down the country are turning to them as a solution. What are heat networks? Generally, heat networks are defined as a system of supply pipes with a centralized heat generator (Energy Centre) that serves multiple domestic or non-domestic dwellings. These are usually in different buildings, but sometimes within a single large building like an apartment block or a university campus.District heating is often used to describe larger scale systems District heating is often used to describe larger scale systems of this sort, where there will be many buildings connected over a larger geographic area. In these systems, although the heat is provided ‘off-dwelling’, it is also common to have more than one energy centre. The principle is that energy for heating (and sometimes cooling) is supplied through the system of pipes, with each individual user being metered for the energy they use. Minimize pipe lengths Heat networks offer a number of advantages but are best suited to areas where there is high heat density, that is to say where there are multiple ‘households’ close together in order to minimize the length of pipes within the network. One of the key advantages for heat networks is their adaptability to use any form of heat generation. A key advantage from an environmental perspective is that they make use of waste heat, from sources such as electricity generation, waste incineration and industry. Heat networks are defined as a system of supply pipes with a centralized heat generator that serves multiple domestic or non-domestic dwellings The scale of the combined heat requirements of all these dwellings also helps the inclusion of renewable energy sources, which may be more difficult and costly to achieve at the individual dwelling level. Overall, their flexibility to use whatever heat source is available, makes them easier to decarbonize in the future.Other key benefits for Local Authorities and Housing Associations have been the elimination of individual gas appliances within dwellings. This has significant cost savings reductions for Local Authorities and Housing Associations where gas landlord checks are eliminated, along with the issues associated with access. City developments Today City Councils and developers are opting for heat networks to provide the heating and hot water for new redevelopment projects. The largest of these is the ambitious Leeds Heat Network, which once completed is set to be one of the UK’s largest new heat networks, connecting 1,983 council homes and numerous businesses in Leeds. The first scheme under the City Region’s District Heating program, the green initiative looks to reduce carbon emissions for the area as well as energy bills for the residents living there.The green initiative looks to reduce carbon emissions for the area Even more innovative is how the network will connect to the Leeds Recycling and Energy Recovery Facility, which burns black bin bag waste to generate heat. In theory this would make the network fully sustainable. There will be back-up support from efficient Bosch Commercial & Industrial boilers, which will only be switched on when required, say the colder months where the need for heat is higher. Climate change targets An hour’s drive away from Leeds is the city with one of the most ambitious climate targets in the UK. Manchester intends to be carbon-neutral, climate resilient and zero waste by 2038 – 12 years before the overall UK net zero 2050 target needs to be hit.To help achieve its ambitions, work has been taking place on the Manchester Civic Quarter Heat Network (CQHN). Manchester hasshown the versatility of heat networks due to the number of commercial buildings it will support The project will generate low-carbon power, heat and hot water for initially six council buildings and some residential properties with the possibility for the network to grow and connect further buildings across the city centre. Some see district heating as a solution solely for residential purposes, however Manchester have shown the versatility of heat networks due to the number of commercial buildings it will support. The project itself has also given Manchester a new landmark, the impressive ‘Tower of Light’, which incorporates the five flues from the technology powering the network. This beacon not only represents the city’s commitment to reducing its carbon footprint but also the innovative nature of district heating. Heating Battersea Power Station The final example lies in the Capital and may be one of the most famous developments in the UK at the moment. Battersea Power Station is not only one of the most iconic landmarks in London, but also the center piece of one of the most high-profile, large scale mixed-use redevelopment projects ever undertaken in the Capital.Battersea Power Station is a high-profile, large scale mixed-use redevelopment project The project involves the development of a district heating and cooling network, with a two-level underground energy centre – one of the largest of its kind. This complex heat, cooling and electricity network will continue to expand as the project continues to undergo its development stages. Looking ahead These are just a few examples of cities taking advantage of district heating and its many benefits, but near all cities in the UK have multiple heat network projects underway. Like with most innovations, smaller urban areas should then follow suit. The importance of district heating will no doubt become more and more prominent. Its ability to power whole areas and multiple buildings can already help efficiency levels, however its potential may be even greater in the future. One key energy transformation that is looking more and more likely is the decarbonization of the gas grid to hydrogen blends and ultimately 100% hydrogen. If these can be utilized in heat networks then the benefits will definitely put us and UK cities in a good place as we continue our journey towards net zero.

Bosch Thermotechnology’s H2-ready boiler shows how green hydrogen can secure tomorrow’s heat supply of buildings. The demonstration boiler was presented at the Bosch Thermotechnology site in Worcester. Although hydrogen is increasingly being seen as an environmentally friendly energy carrier, also in Europe’s building sector, its implementation has so far been rather slow. By developing a hydrogen-compatible boiler, the developers at Bosch Thermotechnology are proving that boilers can be converted quickly and easily from the currently used natural gas to 100 percent hydrogen. Natural gas pipelines A first demonstration boiler of the H2-ready boiler with a rated heat output of 30 kW has been in operation on a test stand since 2017. The H2-ready boiler can initially run on conventional natural gas or a hydrogen admixture of up to 20 percent. As soon as the local network has been switched over to hydrogen, the boiler can be converted to full use of the green gas within an hour by making just a few adjustments. The operation of the H2-ready boiler is similar to that of an ordinary gas condensing boiler Most of the existing natural gas pipelines are almost ready to transport hydrogen, which means that existing infrastructures can be used when switching to the green gas. The operation of the H2-ready boiler is similar to that of an ordinary gas condensing boiler. The important difference lies in the energy source. Hydrogen can be stored indefinitely, thus ensuring constant availability for users. Green hydrogen is climate-neutral and therefore has the potential to lead the heating sector into a green future. Enabling carbon savings Renewable energy is becoming more and more popular in both new buildings and modernization projects. Without additional adjustments such as insulation measures, however, the installation of climate-friendly heating solutions (e.g. heat pumps) in existing buildings is often complex and expensive. The new H2-ready boiler from Bosch makes the difference, as it requires no additional modernization measures and enables carbon savings in every existing building. But climate protection does not mean compromising on heating comfort. The hydrogen boiler from Bosch can react quickly to fluctuating heating requirements due to weather and user conditions and offers the same high performance as a conventional gas condensing boiler. The H2-ready boiler fits into the same footprint as a current gas-condensing boiler, which is a great advantage especially in houses with limited space for the building services.