Why Spruce is our default heat pump design platform

Clients often ask what’s behind the drawings: the LiDAR scans at survey, the room-by-room numbers, the CAD-style schematics in the design pack. The answer is usually Spruce — the heat pump design platform we reach for by default on Heat Loss Hub projects. Here’s how we use it, what the last six months of updates have added, and where we would work in something else instead.

IN ONE PARAGRAPH

Spruce is a UK-built heat pump design platform used by hundreds of installers and designers: LiDAR room scanning, automated room-by-room heat loss calculations, radiator and emitter specification, manufacturer performance data, proposal documents and an MCS-aligned quality management system — one workflow from first site visit to final drawing pack. It is our default platform, and unless a project calls for something else it is where a Heat Loss Hub design gets built. This post is an unpaid, unaffiliated endorsement: we simply think it is the best tool in the category.

On survey: LiDAR instead of tape measures

The measured accuracy this whole consultancy trades on starts with Spruce’s mobile scanning. Walking a room with LiDAR captures its true geometry — bay windows, sloping ceilings, thick stone reveals, the awkward bulkhead over the stairs — in minutes, to an accuracy a tape-and-clipboard survey can’t match on its best day. Windows and doors are marked on the scan as we go; construction observations (verified wall types, insulation evidence, chimney status) attach to the rooms they belong to.

The practical effect shows up in our results. When we say a survey takes two to four hours and captures every room, that’s LiDAR doing the heavy lifting — the hours go into engineering judgement (what is this wall actually made of?) rather than into holding a tape straight across a stairwell.

At the desk: from point cloud to design pack

Back at the desk, the scan becomes the calculation: room-by-room heat losses computed against recognised UK methodology, with our verified U-values and ventilation rates in place of hopeful defaults. Then the design proper: radiator-by-radiator adequacy checks at candidate flow temperatures, replacement sizing where rooms fall short, cylinder selection, and heat pump options tested against pre-loaded manufacturer performance data at the property’s actual design conditions — the exact discipline we describe in the sizing guide, executed in software built for it.

What Spruce doesn’t do — and shouldn’t — is the judgement. It won’t spot that a 1996 cavity fill has slumped, notice the microbore lurking behind a bath panel, or argue with a client about whether the lounge is really a 21 °C room. Software amplifies a designer; it doesn’t replace one. That’s precisely the division of labour we want from a tool.

The last six months: Spruce's update run

The team behind Spruce ships continuously, and the recent run of features has been genuinely useful rather than changelog padding:

Pipework & Drawings — the headline addition: draw new and existing pipe runs and generate detailed CAD-style drawing packs with pipework routing, radiator and emitter specifications and annotated installation guidance. This is the feature our installer network noticed immediately — the drawings answer on paper the questions that used to cost a phone call from under a floorboard. Spruce estimates the automated documentation saves around eight hours per job; on our projects that’s believable.
Faster estimate-to-proposal flow — enquiry data now flows into instant estimates and pre-filled proposals with e-signature, tightening the front end of the workflow. For our design-review clients, it also means we see more consistently structured installer proposals arriving for review — a small industry win in itself.
Deepening MCS-aligned QMS tooling — competency tracking, calibration records and non-conformity management that map cleanly onto the redeveloped MCS scheme’s quality-first direction. The scheme moved toward site quality; Spruce’s compliance tooling moved with it.
Wider integrations — connections to Zapier, Payaca, Simpro, Pipedrive and Zoho for businesses running bigger pipelines than ours.

DESIGNER'S INSIGHT

“The Pipework & Drawings release changed the texture of our design packs overnight. A schematic an installer can build from without ringing me is worth more than any efficiency claim on a datasheet — because every unanswered question on site becomes an improvisation, and improvisations are where good designs go to die. Fewer phone calls, fewer improvisations, better systems.”

Phil
Founder & Lead Designer, Heat Loss Hub

Why we chose it — and why we stay

We tried the alternatives; every serious designer has. Spruce won on four counts that still hold. Survey-to-design continuity: one dataset from LiDAR scan to final drawing, with no error-breeding re-keying between tools. Speed without shortcuts: the automation removes drudgery, not rigour — our assumptions, our U-values, our judgement stay in charge. Documentation quality: reports and drawing packs that architects, building control and MCS installers accept without translation. Momentum: a UK team that ships features working designers actually asked for, on a cadence that suggests they listen. Over 750 UK installation and design businesses have reached the same conclusion — and our vetted installer network benefits directly, receiving design packs in a format many of them already know from their own Spruce accounts.

Default is not the same as only. Where an installer already runs their business inside another platform, we would rather meet them there than force a re-key — which is why we are also trained and subscribed to Heat Engineer, and will build in it when a project calls for it. The reasoning is set out in our write-up on Heat Engineer heat pump design.

For fellow installers and designers reading this: spruce.eco — go see for yourselves. (No affiliate link, no referral fee; consistency demands we recommend software the way we recommend heat pumps.)

What it means for your project

You don’t need to care about software — you need to care about outcomes, and the tooling shows up there: a survey that captures your whole house in one visit, a calculation you can audit line by line, an emitter schedule with the arithmetic shown, and an installer who starts work holding drawings instead of questions. That’s the Heat Loss Hub design pack, and Spruce is the loom it’s woven on.

SOURCES

Spruce — heat pump design software (official site)

Spruce — heat loss surveys & system design

CONTENTS

SEE IT IN ACTION

Every Heat Loss Hub design pack — calculations, emitter schedule, drawings — comes out of the workflow described here.

PROFESSIONAL TOOLS, PERSONAL JUDGEMENT

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If you fit heat pumps and would rather spend evenings on site than in design software, we produce MCS-ready calculations and full system designs in Spruce and issue them in your own name.

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