Working with Contractors

Depending on what you want to do, retrofitting your house, changing your heating system or installing solar power can be simple or complicated, possibly including hiring several contractors, and maybe a project manager too. You may be taking a ‘big bang’ approach or doing it in phases. Selecting competent, reliable contractors that you can trust and maintaining a good relationship with them is very important. This page is not a step by step approach to your retrofit but general advice about how to choose and work with contractors. Much of the advice on this page came from pooled experiences from the energy group members and friends.

Different kinds of contractors - who do I need?

Depending on the size and complexity of the job and your knowledge and expertise, you may need different kinds of people. All of them are in high demand, especially the good ones!

Specialist trades, like plasterers, painters, electricians are good for small jobs but only if you are doing the rest of the project yourself. Most specialist trades people work with a general builder. You might think you just need some plastering done but actually this means removing and replacing skirting boards, electrical sockets and so on. Most plasterers are not qualified to do these extra tasks for preparation and tidy up. So normally you are better off with a general builder.

On the other hand, niche technology such as solar panels, or heat pumps usually requires a specialist installer with a team of tradespeople to cover the common tasks e.g. solar panel installers will have electricians and roofers. They will also have solar panel experts to plan your installation with you. They can be a one stop shop if you only want one thing done with little or no preparatory work. However, if this is only part of the project, you may find they have a blinkered view and do not consider a whole house approach.

A general builder will be able to handle a range of jobs involving building fabric such as insulation. They will expect you to specify the job, though they may be happy to make recommendations, especially regarding different materials which they have used in the past. Builders are often reluctant to try new methods or materials although some are keen to learn new skills.

If your job involves more than one installer or one general building team then you should definitely consider getting a project manager to handle it. Many people who thought they could handle a complicated project involving several contracts have regretted doing it themselves - either because they found they did not know enough to specify the job properly, or to keep an eye on how the work was done - or simply because it was far more time consuming than they had expected. The project manager has to understand requirements, make sure that all the contractors involved know everything they need to know and ensure that the work is done to spec. They also need to keep an eye on the schedule and budget and handle problems that occur, sometimes with changes to the spec and hence the contract. It is very rare for the entire job to go smoothly.

If you are not quite sure of what you need or how to specify it then you need an architect and/or a retrofit coordinator. Either of these can do project management for you too. The role of retrofit coordinator is a fairly new concept, defined in the PAS 2035 methodology. They are specially trained in assessing building energy efficiency and helping you plan your retrofit. They should be able to identify issues such as needing to extend eaves for external wall insulation, identify and head off potential problems (such as condensation) and help with ventilation choices. They can sort out building regulations and if necessary, planning. If your house has heritage construction they will understand the additional requirements and restrictions.

A retrofit coordinator will start by getting a whole house assessment done and then evaluate a set of improvement options. They will help you to prioritise work for your house and keep within budget. If the project has to be done in phases they can advise on the best order to do it in and they can lodge a medium term improvement plan for your house, which is like a specification for future improvements.

Retrofit coordinators are thin on the ground, as yet, and some are qualified but not registered. If they are not registered with Trustmark they will not be able to offer the same level of guarantee, or lodge plans, but they may still do a good job. Registering is expensive and requires extra insurance.

Checking qualifications

The qualifications to look for depend on the role and what you want to have done. A registered retrofit coordinator will be on the Trustmark register. Many architects are members of the Royal Institute of British Architects (RIBA). You might also want one who is a member of the AECB (Association for Environment Conscious Building).

Solar panels, heat pumps and other renewable technologies need to be installed by someone with MCS certification - but this is a fairly general requirement and not product specific.

Most product warranties require that the installers are appropriately qualified. A warranty may be provided either through a trade association e.g. SWIGA for solid wall insulation, or by a product manufacturer. For example, if you have a Mitsubishi heat pump installed, then you should be offered a homeowner guarantee from them. If you are not offered this it is probably because your installer has not done the necessary product training.

If you are not sure, ask your installer if they have worked with the product before, or if they have done the CPD training (Continuing Professional Development) for the product.

Bear in mind that where there is a team of people involved they will not all be qualified to the same degree. Make sure you know who is the expert, and avoid asking the others questions. They may say they don’t know, or they may offer inappropriate advice because they do not fully understand the issues.

It is perfectly reasonable to ask for references when taking on a trader you do not know.

When to hire locally/nationally.

Generally we recommend that where possible you choose a small, well established firm (or sole trader) that is locally based and has a good reputation. Friends and relatives are the best sources. A firm that relies on recommendation has a reason to do a good job, not just an adequate job, or a quick one. Also, if you use someone local and it turns out well you can use them again. Building a good relationship over time is good for both you and your contractor.

You can find a list of local contractors who have worked for Open Eco Homes hosts on the Cambridge Carbon Footprint website here.This is not exactly a recommendation but you can look at the case study (and maybe watch the tour video) to see what they did.

Sometimes it is necessary to use a firm that is based further away. For example if the product is very new or very specialist there may not be any local people with the capability to help you.

If you have a good relationship with someone but they cannot do your job this time, you can ask them to recommend someone who can. Contractors are good at networking and they are unlikely to recommend someone who is likely to do a bad job because it will reflect badly on them.

RetrofitWorks is perhaps the ultimate for contractor networking. It is a co-operative for contractors including retrofit coordinators.

Doing your homework

There are two things you need to know about:

  • General options for your project (e.g. different types of product)
  • Specific information about your house

Generally, the more you know about the issues and options for your project the better. However, if you are hiring an architect or a retrofit coordinator that is independent of the installers, then you can expect them to have a reasonably wide knowledge and be able to give you guidance. Do ask them questions about different options. What are the pros and cons? What maintenance will be needed? What factors could affect performance?

There is often a great deal of general advice on the internet via blogs, discussion groups and so on.

You should also know as much as you can about your house energy performance and your energy requirements. This is critical for predicting what you might achieve with renewable energy or batteries. It is also important for considering savings from energy efficiency.

Before you start, make sure you know your energy consumption, and how this compares with the assessed energy use. If there is a significant difference, you need to understand why and how this will affect the project results. You should know your consumption patterns through the seasons, not just over the year. If you are considering PV panels or batteries you really need to know your consumption through the day. This is normally possible with a smart meter.

Getting energy consumption data is critical if you want to be able to compare usage pre and post install.

Getting access to smart meter data

If you have a SMETS 2 smart meter then there are a number of routes to viewing and downloading your data. Your smart meter remembers your energy use for 18 months in half hour intervals so you should be able to get data that far back, or to when you had the meter installed. Some solutions allow data download, others only offer visualisation with charts. Octopus Watch is an app for Octopus customers and this does support data download.

If you cannot get data from your supplier, there are other solutions offering visualisation charts and sometimes data download. Third parties cannot access your data without permission. This is regulated by the DCC.

These support data download.

Several firms offer app solutions such as Loop and Bright

If you can recommend other solutions please let us know.

Keeping on good terms

Most contractors like clients taking an interest up to a point - but not interfering. A daily chat about how things are going is good. For complex jobs it is normal to have a fortnightly progress meeting and this is the best time to ask questions.

If you have a project manager, then it is their job to give instructions to the contractors. You can ask questions but not give directions. If you have an urgent concern, contact your manager.

Most small firms need payment in instalments. This is essential for their cash flow. If you do not pay promptly this can cause bad feelings and delays.

Changes to the contract

Most contracts are fixed price to start with but something often comes up that means extra work is required so the contract price has to increase. If your contractor has underestimated other costs and are already running over (their) budget, then they are likely to try to over-charge you for the new tasks to make up for their previous losses. The more you know about what things typically cost the better. It helps to have a fairly detailed costing to start with so you know how much they are charging for labour and different kinds of materials.

In any case, if they just give you a total price with no breakdown of costs, it might mean they have not thought the job through properly and this can mean trouble later. If you have a breakdown you can compare different quotes to see how they vary.

Being realistic about timescales

Projects almost always take longer than you expect and plans often overrun. A lot of jobs are weather dependent. There can be difficulties with supplies. There may be preparatory work, including ground works, and sometimes you need to get utilities to do things in advance.

For example, an electric storage boiler that runs off peak puts a high load on your electricity supply. You need to store a whole day’s heat in a few hours and if you do not already have one you may need to be upgraded to a 100 Amp supply. This has to be arranged through the DNO (distribution network operator - in this area, UKPN). The upgrade is free but it can take months. For some jobs you need permission from the DNO and there may be fees. After-care and monitoring After the project is completed, how do you know it is delivering the expected performance? Most small firms run on very small margins and do not have the capacity to do routine aftercare so this is your job. You need to make sure you know what to expect and how to measure it. If it is a new heating system, what energy consumption/efficiency should you expect? For solar panels, how much should they generate? For a battery, what is the throughput you should be getting? Most systems have some way to collect data about their performance.

Even if you are doing the checking, it is best to agree with your contractor that you will do this and let him know when you have done it, even if it is successful. Ideally, performance should be part of the contract but this is rare.

It is not advisable to wait for a whole year of data before checking performance. The earlier you can identify a problem the better. Your contractor will still remember the job and you won’t lose a whole year of bill savings. Ideally you should be able to check this within a month. For solar panels, you could ask a friend with a similar size array what they have been getting. However, for insulation or heating systems delivered in the summer you need to wait until you need heating to check it properly.

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