Renovating on a budget - ideas to simplify your project. Don't be afraid to change your style!

We've all wanted to do home improvements to increase the value of our homes. Maybe you're looking to sell and you want to get the best offer but you don't want to spend a fortune getting there? There's a fine line between adding value and spending a lot! If you're looking to stay in your home for a while you might have more reason to spend a little more. This, over time will add extra value to your home so you won't be out of pocket. To know what improvements to do, you really need to work out what bracket you fit into. I recently wrote a blog about updating kitchens and what they can do for your home. If you're looking at improvements then this is a good place to start. A lot of people look for a feature kitchen. Our lives have changed and, as I said in the last blog, we want, need and expect more from our homes now more than ever. You have a few options with the kitchen and starting off at the most expensive end, you could add an extension. Gaining more space for your existing home is often cheaper than buying a place that already has this space. You don't incur the moving costs, the solicitor's bill and the likelihood is that you would still want to decorate and put your stamp on it. If you're just looking to update your existing kitchen you could consider changing the cupboard doors and work surfaces. This is a quick and easy way to revamp what you already have and in terms of money and time it shouldn't be a big job. There is also a new trend where you can quite literally cover your existing units and work surfaces or even paint them. This is obviously the cheapest option and you can do it yourself. However this isn't a long lasting solution and is probably only best if you're thinking of staying in the property and using it as a 'stop-gap' until you know exactly what you would like, or until you have managed to save for your dream kitchen. Depending on what home you have you might even have some period features that you can reinstall, revamp or uncover. Maybe you have a fire place that has been boarded up. This could easily alter the feel and design of any room. If you're fortunate enough to have these features then make use of them. I know that not everyone has a garden but if you do then get those green fingers out. This is something that you can do yourself if you're wanting to complete it on a smaller budget and all of your money can then be spent on plants and accessories. However, if you would like the tailored professional look then employ a landscape gardener. They really do know what they're doing and a landscape gardener can add some real value to your home. There are many sites online with some excellent ideas on home improvements to suit any budget. Check these out for example. https://www.money.co.uk/guides/9-easy-ways-to-add-value-to-your-home.htm https://www.frugalandthriving.com.au/8-ways-to-improve-the-value-of-your-property-without-breaking-the-budget/ Essentially whatever you want to do to your home, whether it's for yourself or to entice a buyer/renter there are many ways to do so. There are varying different levels of improvements and with them come different levels of budgets. You will and can do whatever you want to your home. It is your home, your style and your money, don't be swayed by someone else.... trust your instincts!

Eco building- construction at its best. Top tips on which materials to consider when building green.

So we are at the point where eco homes are homes of the future. We need and want them to sustain and one of the hardest decisions to make is what materials to use. Firstly you need to think about the look of your home; your materials will play a massive part in the aesthetics of your build. You need to find materials that work together with your idea, the style of your home and ones that provide the best eco benefits. There are many materials that you can consider and I unfortunately don't have the time to talk about each and every one so, I thought it was best that I discussed the most obvious. Starting with timber, you have the option here to choose sustainably grown timber which not only provides you with natural materials but also allows you to essentially give back what you take. You also have the option of using recycled timber which can add to the 'look' of your home.  Natural stone is another good material and limestone for example is fire-resistant, sound-absorbent and strong. The downside here is that this material isn't replenishable and it is not always local so you will have to consider the transportation process. Concrete is another material that is often considered and in fact, at the moment seems to be on-trend. It is strong, low maintenance, fire resistant and ages well. This is a man-made material and the process isn't often as eco friendly as you might think.  What you might not have thought about is how your materials are sourced, how you get them to your site, how far they have to travel and if they are replenishable. These are all factors that play a part in your build. If you're set on building an eco home I would imagine that the impact on the environment plays a big part in your choice of materials. You can build your home to the highest eco standard but if the production process itself contributes harmfully to the environment then you may have forgotten your goal. Your eco future will be mapped out once you have your home, your bills will be lower and your environmental impact will be small in comparison. Here is a site that has some amazing ideas on different materials that you can use, some you might not have even thought of let alone considered. https://elemental.green/10-eco-building-materials-revolutionizing-home-construction/ Sometimes you may think that an idea seems a bit strange but do your own research, things are only strange when we don't understand them. From knowledge we get growth. Eco homes are thankfully here to stay, lets play our part in providing a sustainable eco friendly future for the generations to come.

SAP testing....yet another compliance. How being the best will benefit you!

SAP testing / calculations  aka Standard Assessment Procedure is the assessment used to test your build's performance. I know there seem to be quite a few  procedures and testings to get through and I, for one, know how daunting this can sometimes feel. But, if you knuckle down and plan from the beginning you won't have anything to worry about. These calculations  will soon become second nature. SAP assessments essentially enable the Government to compare builds across the UK. Imagine being at the top of that table! Plan with your architect right from the beginning. As I have said time and time again, use the resources you have, utilise peoples' knowledge and experience. Experience is something that can't be taught through books. You would be able to employ a SAP assessor who will be able to ensure that you achieve the highest possible standard to pass your assessment should you employ them from the initial stages. Essentially they will work from the plans that your architect has drawn up. These plans need to be on point. (I can't stress how important it is to have a close, comfortable working relationship with your architect.) This is something that will evolve over time, although you will know fairly instantly if you will be able to work together or not. You need to be able to communicate well, you know what you want and your architect knows how to implement it. This will be one of the most important relationships you'll have and you'll likely want to use the same architect for each of your projects. Essentially your SAP assessor will work from your architect's drawings and will provide you with your predicted energy performance certificate. The assessment will quantify a home's performance in terms of energy . This will determine the environmental impact of the building while maintaining a comfortable living space for all occupants. The ratings provided are from 1-100 and based on the energy cost of that build over a year. The higher the score the lower the running costs for that dwelling. The results are based on factors such as the heating and hot water systems, the internal lighting, the renewable technologies that are used within the building and the elements of the structure.  The SAP test will obviously need to be finalised at the completion stage. From your final assessment you will receive your EPC (energy performance certificate). Remember that your results will be logged in the central register. Construction is one of those industries where there are many different levels. For example you can produce top quality builds, mid-range or lower end so you really do need to know your clientele. Having said that, working to a budget doesn't mean that you have to take a knock with your compliances. Planning and working closely with your architect and assessor will allow you to achieve the best results possible. In fact, it can actually be more costly to make alterations once the work has been completed. Do it right the first time, not just right but the best it can be. By getting excellent results in your SAP calculation you'll receive lower running costs from your build and achieve the best results will allow you to stay ahead of your competitors and who doesn't want that?

Building Regulations - working together as the dream team!

Why do we have Building Regulations? You wouldn't be human if you hadn't asked yourself this question before. I know first hand how frustrating these regulations can be! You feel you're getting somewhere and then you find you're tied up in red tape. These regulations don't exist to stop you from building your best home, they're here to help you build your best home... safely. That's the key, without them we wouldn't have safe secure builds and no matter how much red tape there is to get through we don't want to have homes that are unsafe; bottom line. Building Regulations evaluate all aspects of your build; foundations, damp-proofing, structure, insulation, heating, sanitation, accessibility and fire safety just to name a few. The regulations are here to ensure that work is carried out safely. They also protect you and others from unsafe and unregulated builders. Regular site visits make sure that the work that's being carried out is in compliance with the measures. You can always ask questions while you have your Surveyor there. Take advantage and if you have anything that you want to know, ask. It can be an extremely costly practice to 'fix' or alter things once the work has been completed. Assuming you have the right employees then you won't have anything to worry about. Your trades will know their crafts so trust them. You hired them after all. If you're in the business of eco builds (and this is the way that most companies are heading), then the Building Regulations are on your side. The Government has a deadline of 2050 for net zero carbon emissions. That might sound a long time away but don't be fooled, that will come around quickly. If you haven't thought much about the eco side of building then there is no better time than now; soon you won't have a choice. The regulations also aim to improve the conservation of fuel and power, protect the environment and promote sustainable development. This is just part of the role of the Building Regulations. What you must remember is that anyone who works for Building Control will attend regular courses and training and this can be used to your benefit. As I said, ask questions and utilise their knowledge. If you need a trade they might even be able to put you in touch with reputable people? They are on your side although it might not always seem that way but trust me, they're not your enemy! If your build doesn't pass the Building Regulations and you ignore that fact then there will be serious consequences. Not only will it be costly to rectify but you could even find yourself in a position where you have enforcement involved. Enforcement have the power to remove an unsafe build that is not compliant. This isn't something you can bypass and it isn't something you should bypass. Not only do these regulations help protect the public from unsafe builds, they also help keep the quality of builds high. We are building houses for the future; we need to make sure they are built ready to take on the next generation and generations after that.

Eco building at its finest- what can be achieved....

From inspiration come ideas! I am an advocate for eco builds to whatever level. The more we can protect our environment the better it is for the generations to come. There's so much material out there that can lead you forward into the eco sector if you're not already convinced, or if you're looking to get a bit more information. Either way it is such a good idea to research. Some of the best ideas come from inspiration and inspiration comes from seeing exactly what you can do. Sometimes it is good to show everyone what we can achieve. All you need is a good workforce, a plan and some clever ideas.  I am going to show you a few of the best, most extravagant eco builds the UK has seen to date. These are not the cheapest of cheap but they can really show you what you can achieve. BedZED, is the UK's first large scale eco village.  This village was completed in 2002 so has been established and working now for 18 years. I'm not saying it didn't have problems but it was ahead of its time. I'm sure if this were to be built now there would be updates made. Things can change a lot over time and with experience, new technology and advances that come into play, it would be hard not to make small changes. Having said that, this village is so forward thinking and is certainly standing the test of time. It comprises 100 homes, office spaces, a college and community facilities. It really is a purpose built eco village and just proves what can be done when planned and executed well. The complex benefits from green buildings, renewable materials, innovative heating, reduced energy consumption and self sufficient heating and electricity.    You can read up about BedZED here https://www.bioregional.com/projects-and-services/case-studies/bedzed-the-uks-first-large-scale-eco-village It is not just homes and villages that are taking the environment seriously, a number of offices around the country are also joining in. They are making the future greener and they are cutting their bills down in the process. For example there are offices such as PwC HQ in London which apparently have a biofuel combined cooling heat and power system, low flush toilets and green walls just to name a few, in turn lowering their impact on the environment and maintaining low bills off the back hand.  Co-op HQ in Manchester has also joined the eco train. The building is configured to optimise passive solar for heating, cooling and day lighting. The solar panels apparently provide 80% of the hot water. This is just the tip of the iceberg. If you would like to look further then take a look at the links I've suggested. These give you examples of builds that have applied eco technologies and gives you an insight of what can be achieved.  There are so many examples I could show you and I know these are at the larger end of the scale but I am fascinated by what can be done with the technologies that we already have. These can be applied, evidently to any size or shape of a build, whether its a village, office block, or your home. This is the future and it is exciting.  If you would like some more inspiration, please take a look at these sites. There are many builds out there that are really flying the flag for eco; the quicker we get on board the better. Just look at what can be achieved. Construction really is an amazing industry.  https://www.pbctoday.co.uk/news/planning-construction-news/five-of-the-uks-most-impressive-eco-buildings/40160/ https://c-r-l.com/content-hub/article/6-uks-best-eco-buildings/

New Part L regulations - will gas heating be gone forever?

The amended method of calculating home energy efficiency is changing the heating system industry forever, and quicker than you may think… With the new Part L regulations set to be used in the near future, I think there will be an immediate retreat from gas central heating systems and an adoption of electric heating.

Gas
Pro’s	Con’s
·         Effectiveness in relation to cost	·         Costly installation from scratch
·         Faster warm up time	·         Annual maintenance (excluding breakdowns)
·         Still runs if electric cuts out	·         Short life span in comparison to electric
·         88-90% efficient in most cases	·         Isn’t a green source of energy
·         Can produce air temps 25 degrees warmer	·         Inefficient to the point they harm our planet
·         Burns cleaner than other fossil fuels	·         Wastes energy through pipework

 

Electric
Pro’s	Con’s
·         Same fuel factor rating in SAP as gas	·         Potentially more expensive in the long run
·         Cheaper and easier installation	·         Longer heat up time
·         No Maintenance costs	·         Chance of overloading your electric system
·         100% efficient	·         No warmth or water if power cut strikes.
·         No noise emission or limescale build-up	·         More expensive breakdown costs
·         No restrictions on property layout
·         Clean and respectful to the environment
·         No chance of harmful gasses congregating

 

 

We will see a 55% reduction in emission factors for electric heating bringing it very even with gas emission factors.  The change comes as we’ve seen a massive decarbonisation of the electricity grid in past years. Over 30% of electricity is now being generated from renewable sources.

Although electricity is the way forward, we still need to consider the heating of larger homes (which gas is better suited for). Most importantly how will the end user be affected? With electricity costing on average 14.37p per kWh and Gas costing 3.80p per kWh.

Are providers going to lower prices with obvious increase in demand?

Are we entering an era of fuel poverty on top of ever rising house prices?

What incentives will the Government put in place to assist the people of this Great Country?

Kitchen inspiration - The perfect design

When you get to the stage of designing your kitchen you have a lot to think about. Who is going to be using it? Is it going to be the heart of the home? What is your style? etc etc. I don't want to keep talking about Covid19 but we have to reflect in the aftermath. What has it left us with? I recently wrote about how the home has changed for us and how we need more from the same build. Essentially our homes have to become more versatile as our needs have changed and the kitchen is no different.  What do you want from your kitchen? Long-gone are the days where kitchens were just used for make dinners, now they now need to be able to do so much more. Perhaps you would like to include a snug? Maybe you have a young family and want a play area so that you can keep an eye on the children while making food? We all know how much kids eat and how many times a day they ask for a snack! Maybe you even find it hard to actually venture out of the kitchen so it needs to be the room where everything can happen. Perhaps you want bi-fold doors so that you can bring the outside-in and utilise the space and expand it as much as you can?  You really need to think of what you want from your space. This applies to any room in the house and needs to be considered at the design stage. Take a look at Pinterest or Instagram and get some images in your head, make a collage even...get all your ideas down on paper. There are plenty of people who will be able to help with your design. A lot of people tend to go and get advice from a kitchen designer. This is an excellent starting point. Use peoples' knowledge and advice where you can and utilise their experience.  Check out here https://www.pinterest.com/TMUStone/dream-kitchen-inspo/ for some ideas. Think about your colour scheme, storage and use of space. The latter is the main thing that you need to consider. Bespoke kitchens are becoming more popular for this very reason. You can essentially design your kitchen around your needs. These are by far the most popular types of kitchens.   People are no longer going out to eat as before (for obvious reasons) and this for the timebeing has now become the new normal. So we now need our kitchens to be adapted to suit the social gatherings that are/will take place. Larger quantities of food are being consumed and need to be stored. There are walk in food cupboards to maintain supplies and keep organisation and large fridge freezes and big double ovens. Utility rooms are also expanding, essentially becoming the laundry room, with washers, dryers and room for all of the extra necessities such as vacuum cleaners.  The kitchen has always been an integral part of the home, but it is now so much more than that. We need and expect a lot from our kitchens and on top of that we even need them to be equipped to actually cook in. Their role has evolved and never so much as now. We want them to be an office, a play area, somewhere to relax, somewhere to entertain and somewhere to cook and store food.  Think about what you need and want and don't be ashamed to go after your dream. There are many solutions out there, many ways in which your room can be adapted to your needs. This is going to be the heart of the home, that's what kitchens are about. Think of your family and what they need from it too. You might need to splash out here, but it will be worth it in the long-run. If you do this right, it will be for keeps.

Sound testing - fail to prepare and prepare to fail. The importance of top marks!

Here it is again...sound testing! One of the many compliances that you're going to have to adhere to if you're on any building project. Don't fear, this isn't scary and you can achieve excellent results which will not only be good for your build and whoever lives in it, but also for you...build your best. Now as I've said before with many of the compliances, you really do need to start planning from the design stage to ensure that you get the best from your build. There are many details in the actual design of the building that can seriously impact the testing results. It is by far the better option to overcome any issues before you start construction. Sound testing is a requirement of the Building Regulations Part E and relies heavily on the acoustic design of your build. There are two main areas to consider when discussing sound insulation; airborne sound and impact sound. Airborne sound refers to noise that will come from things such as televisions and radios and impact noise refers to sound from things like footsteps. Essentially to ensure that you're going to pass the sound test you will need to plan, plan and plan! Make sure that everyone knows exactly what it is that they're supposed to be doing. Ensure that there is always an accessible copy of the design plans (this should be standard practice on any site anyway) and make sure that you regularly check your construction against your plans. If there are any mistakes along the way then they should be picked up early on. Any alterations that are made throughout the course of construction should be considered with regards to sound testing and, in fact, all other compliances. You will be surprised that even the small deviations in design can have a serious impact on your build and its effectiveness for these testings. You may want to get a sample test before test day so that if you need to you can make any changes before the test. Hopefully this won't be the case and I'm sure with the amount of planning and care you've taken with your design then there will be no need to be worried about test day. It might be beneficial to get help from a consultant, feed off their knowledge and advice, utilise them and what they know. They will have tips and tricks that you might not have even thought of. Involve them in the planning and design if you can. You will be surprised at what they will be able to pick up from your design alone. If you want to get the best out of your sound testing (and you should) then you need to put everything you can into ensuring that your build reaches its highest potential.  You'd be surprised at what small changes can make to your results.  Obviously only organise your test once you know that your build/site is totally ready! Fail to plan and plan to fail; the age-old saying that quite honestly just fits the bill.

Fire safety rules and Building Regulations explained

When talking about Fire safety rules we can suddenly be caught up in a whirlwind of regulations. What we have to start with is to identify the different groups.  Firstly, you have the regulations for the site itself. These will keep your site running smoothly and safely and ultimately should be self explanatory.  Then you also have the fire safety regulations for the build itself. These are the rules and regulations that you need to comply with to ensure that you build a safe and secure home. These are outlined in Part B of the Building Regulations. They aim to provide the following; escape routes, preventing the spread of fire inside the home and also to any neighbouring properties and allowing access to the fire brigade. Unfortunately, we have witnessed in recent times, situations such as Grenfell. No one can forget the destruction and devastation caused and ultimately the highest price paid; lives. This is a tragedy that shouldn't ever have happened. If we can take anything from this, it is the importance of fire safety in buildings and why we should take every step seriously. I know how difficult these compliances can be and how much stress they can cause but just remember you can seek advice and help along the way should you need it.  I could talk about fire safety forever, with all the different things you can do but I will name just a few. Essentially each build will need its own assessment. For all new homes and extensions you should have mains operated smoke alarms fitted. These should be fitted and placed within the requirements of the regulations. If you have any open plan areas then these should also have an interlinked heat detector.  You will need to create access for emergency vehicles. Fire engines must be able to get close enough to the building. There should be an adequate supply of water that is accessible for the emergency services. There should be access to every part of your build. This can and should be considered at the design stage. It is a vital part of your build and regulations. If emergency vehicles don't have access to each section of the build and a fire was to break out, it could easily take over and spread. To ensure the safety of others you will need to make sure that there are no combustible materials close to a boundary. This should help to contain a fire should one break out and stop or at least slow it down from spreading to any neighbouring properties.   There are so many ways in which you can ensure that your property is compliant and as safe as possible. I have just briefly laid out a couple of points here and barely scratched the surface. The home that you're building will require its own assessment. The rules and regulations can vary slightly depending on the building. For a more in depth look into fire safety and building regulations, check out this site https://www.homebuilding.co.uk/part-b-fire-safety/  they have some excellent information.  Always ensure that you abide by these rules and don't cut corners. Safety isn't something to cut back on! Plan ahead, research and get help if and where you need it. There is no shame in asking for advice.

Passive House standard...achieving the results!

Passive houses work by making sure that heat is not lost through the fabric of the build. These houses are built according to a set of design principles, which are set to ensure that the build is eco friendly.  I'm sure you realise that a Passive house is all about the architectural design. This is vital for receiving the correct results. The design needs to ensure that it is airtight. ATSPACE is an excellent source of information on all compliance testing but essentially they will be able to help you with the air prerssure testing  concept and design of a Passive house.  As I mentioned, the basic principle of a Passive house is to make it virtually airtight and super insulated. These houses also use a heat recovery ventilation system (MVHR) which essentially makes sure that your build will continuously have circulation of fresh air. The stale air that leaves the building passes the heat back into the incoming air which means that the total heat loss is minimal.  In summer, this process is reversed making sure that your home stays cool and that it maintains the circulation of fresh air. You won't regret undertaking one of these builds. The comfort that it will provide is amazing, and these builds are brilliant for both us and also the environment.   Passive houses are essentially a concept that will ensure the longevity of the build. Houses these days are being 'future proofed' and to do this efficiently they really need to be eco friendly. This doesn't just help the environment or even the Government's timeline but it ensures that the build itself is cheap, comfortable and efficient to run. There are many materials that can be used to build a Passive house as long as the principles of Passive house are adhered to.  When talking about these builds or any other eco builds for that matter, you will hear a lot about the thermal envelope. This is key and includes the outer walls, windows, roof, foundation and doors. This essentially prevents the heat loss from a house through the interior/exterior of the build. This is where your MVHR (Mechanical ventilation with Heat recovery) system will come into play.  Regardless of where you are in the world Passive builds and eco houses are here to stay and they are the future of construction. They make use of environmental elements and combine them with clever construction techniques, excellent design and suitable building materials.  The long-term savings from a Passive house can be huge. These are certainly homes that are designed for the long-run and the money that you invest in the build itself will be returned via cheap running costs throughout its lifetime.  The Passive house standard dictates no particular methods of construction, which means that your architect can design your build based on your desires and needs. The requirements are that you build to Passive house standard and you will need a certified assessor to assess your build. The future of construction is exciting, it is eco friendly and it is bright. Don't be afraid of Eco builds. The external design can be stunning, the materials can be versatile and the builds themselves will live on for years to come.

Construction - what is the new normal?

For the last few months the world has changed. We are all trying to find a new normal and the construction site is no different. There are going to be many changes, many things that aren't as they were but that doesn't mean that this has to be a bad thing. Firstly, the things you might notice are the differences on site such as the new safety measures that are put in place, the social distancing and the slower pace of construction. Then we have the length of time it takes to get materials, the difficulties that you might face with your usual suppliers, seeking out new materials, reopening of sites, planning and maintaining site safety under the new rules, just to name a few.  Construction has been reshaped in the type of projects that are needed. Where there used to be a demand on hospitality, retail and entertainment that demand is no longer there. I'm not saying that these won't ever need to be built again, but whereas before you used to have these complexes that would keep some companies running, you will likely find that there is no longer the need, well not right now at least. These types of builds have certainly taken a backseat, understandably but homes are and will always be in demand as people will always need somewhere to live but even these have changed. Our needs as consumers are no longer the same. Buyers expect and want more from the same build. The pressure is on for construction to not only deliver but to deliver a new normal.  We need to make sure that whatever our role in construction is we're ready to adapt. We have proven over the last few months that there is nothing we can't do. We have come through the hardest of times and are uncertain of what the future holds. We are not out of the woods yet and we are still adapting to our new way of working. But by now, we should have working sites, employees should be back with a new working model and construction should be taking place. I imagine that some of these new ways will be here to stay, certainly for the foreseeable, such as the distance working. We all know how dangerous construction can be and Covid19 is making us all evaluate our sites ensuring that safety is first and foremost, which can't be a bad thing. The use of technology has also been accelerated, allowing us to perform tasks that were usually only done in person or tasks that would have taken us longer or ones that would have needed more than one worker at a time.  Projects are generally taking longer to complete and we are looking at new methods to help us get back on track. Now I know construction workers are unable to remote work but there are some people who will be able to, for example support staff. There are many ways construction has changed and many things we have had to adapt to. Houses are changing, our needs are changing and our ways of working are changing. Construction workers are now on a mission. We have to find a way through all of this madness and deliver on the new normal.

How are the new SAP calculation changes going to affect me ?

As you may or may not be aware there are some important changes happening to the SAP calculation....

Below is an overview, make sure you become familiar with them! If you are unsure speak to Atspace who will be able to talk you through them and advise you on what you need to know.

 

• CO2 emission factors, primary energy factors and fuel prices, have been updated
• Default distribution loss factors associated with heat networks have been increased
• The assumed heating pattern has been changed to a consistent daily pattern for all days of the week
• The assessment of summer internal temperatures has been refined
• Additional design flow (heat emitter) temperature options have been provided for heat pumps and condensing boilers, which affect their efficiencies
• Default heat pump efficiencies have been updated
• The calculation of lighting energy has been updated to allow recognition of new lighting types with higher efficiency
• The options for entering heat losses from thermal bridges have been revised
• The calculation of hot water consumption has been adjusted to account for shower flow rate
• Battery storage is now accounted for in calculations for PV panels
• The impact of PV diverters is now taken into account
• The over shading factor used for the PV calculation can be taken from Microgeneration Certification Scheme data