When it comes to solar panels, heat pumps, or battery storage, the installer you choose can make or break your investment. Unfortunately, the rapid growth in demand for renewable systems has led to a rise in inexperienced or unqualified installers especially in high-value property projects where budgets are larger and expectations are higher.
In this article, we’ll walk you through the 7 essential questions to ask before hiring a renewable energy installer so you can avoid costly mistakes and get the expert service your home deserves.
Why It Matters
Installing renewables in high-end homes, barn conversions, or self-builds isn’t the same as doing a basic solar job on a new estate house. These projects require technical knowledge, aesthetic sensitivity, and careful planning to ensure performance, comfort, and visual harmony.
Choosing the wrong installer can lead to:
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Poorly sized or inefficient systems
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Damage to your property’s appearance or structure
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Expensive rework or future system failure
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Warranty issues or non-compliance with regulations
Here’s 7 Key Questions to Ask Any Renewable Installer
1. Are You MCS-Certified?
Why it matters:
MCS (Microgeneration Certification Scheme) certification is the baseline for renewable energy installations in the UK. It ensures the installer follows proper procedures and that you remain eligible for any government grants or incentives (like the Boiler Upgrade Scheme or SEG payments).
Custom Renewables is proud to be MCS-Certified.
2. Can You Show Me Case Studies or Projects Similar to Mine?
Why it matters:
Self-builds, barn conversions, and heritage homes come with unique challenges — complex rooflines, thick stone walls, or planning restrictions. You want an installer with proven experience in properties like yours, not just new-build estates.
Custom Renewables can offer photos, client testimonials, and before-and-after shots of real installs. You can find case studies in the knowledge hub section of our website. We are also happy to organise site visits for customers to see examples of our previous work.
3. Do You Offer a Bespoke Design Based on My Property’s Needs?
Why it matters:
A “one-size-fits-all” system won’t cut it in a high-end home. You need a tailored design based on:
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Energy usage patterns
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Orientation and shading
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Architectural integration
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Long-term energy goals
Custom Renewables will carry out a full site survey, load assessment, and heat loss calculation before quoting your project. We design a bespoke system based on the individual requirements of each customer.
4. What Brands and Warranties Do You Use?
Why it matters:
Not all solar panels, batteries, or heat pumps are created equal. Some cheap systems have shorter lifespans or limited support. Be sure your installer uses premium, trusted brands and offers solid warranties (ideally 5–10 years or more).
Pro tip: Ask if they’re an approved installer for those brands — it often extends warranty and support options.
Custom Renewables only use reputable, reliable brands that are at the top of their game within the industry. We are proud to be approved installers for Veissmann, Valliant and Nibe.
5. Do You Provide Ongoing Support and Maintenance?
Why it matters:
Even the best systems need periodic checks or occasional troubleshooting. You want an installer who will be around for the long haul, not someone who disappears after the job is done.
What to ask:
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Do you offer maintenance packages?
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Can I monitor my system remotely?
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What’s your response time if I have an issue.
Customer Renewables are always on hand to deal with any issues should they arise. We also offer a comprehensive Maintenance and Service Plan with every heat pump installation. Our plan is designed to provide a dependable, professional, and cost-effective service. It ensures that your heat pump operates at its peak performance throughout the year.
6. How Do You Handle Aesthetics and Design Integration?
Why it matters:
In premium homes, visual impact is just as important as performance. Will your panels clash with slate tiles? Is the heat pump going to be visible from the driveway? Will ducting or cabling spoil the interior?
A high-end installer should work with your architect, builder, or interior designer to blend form and function seamlessly.
At Custom Renewables we are frequently working alongside other contractors to bring the very best results to our clients. We have our own team of contractors that we can recommend or happy to work with contractors as appointed by our customers.
7. Can You Explain the Payback and Performance Expectations Clearly?
Why it matters:
You need realistic, transparent numbers — not sales hype. A good installer will provide:
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Estimated annual savings
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System performance projections (kWh/year)
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Payback period based on your actual usage
Beware of companies that overpromise returns or dodge clear data.
Custom Renewables will always provide you with an estimate of the numbers you can expect from your installation. You can also check out the performance of some of our previous customers systems here
Final Thoughts: Invest in Expertise, Not Just Equipment
Renewable energy systems can add real value to your home — in comfort, efficiency, and property resale — but only when installed correctly, sensitively, and intelligently. Don’t settle for generic solutions or slick sales pitches.
At Custom Renewables we specialise in bespoke renewable energy systems for high-end homes, barn conversions, and self-builds. Our team combines technical expertise with architectural awareness — so you get clean energy without compromising your home’s character or performance.
Thinking about a project? Contact us here for a free consultation or property assessment today.

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