CavLab Engineering, tested and explained.

CavLab

Engineering, tested and explained.

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Splash, Frost and False Alarms: A Winter on the Garden's IP-Rated Sensors
Hardware & Standards

Splash, Frost and False Alarms: A Winter on the Garden's IP-Rated Sensors

Five outdoor smart sensors, one British winter and a set of IP ratings that promised more than they could deliver. We compare claimed ingress protection with condensation, cold batteries and the realities of a wet garden.

Load, Heat and Paperwork: Measuring a 7.4 kW EV Charger on a Legacy Consumer Unit
Energy & Retrofit

Load, Heat and Paperwork: Measuring a 7.4 kW EV Charger on a Legacy Consumer Unit

A 7.4 kW charger is a 32 A load that runs for hours, not minutes. We instrumented one on an older consumer unit to see where thermal behaviour, voltage drop and diversity diverge from the installation paperwork.

Hardware & Standards

Listening at the Router: A Week of Traffic from a British Smart Home

Smart thermostats and hubs promise convenience, but their network behaviour is rarely examined. Using a mirrored WAN port and local DNS logging, we mapped a week of traffic from common UK smart-home devices and tested how much control survives without the cloud.

Eight Hundred Watts, One Grey Season: What a Balcony PV Kit Really Delivers
Energy & Retrofit

Eight Hundred Watts, One Grey Season: What a Balcony PV Kit Really Delivers

Plug-in solar kits are being discussed as a simple route to domestic generation, but a British winter is a stern test. We instrumented an 800 W balcony kit for six months, logging yield, inverter behaviour and the arithmetic behind payback.

Down the Plot, Up the Stack: A Season of LoRaWAN Sensors on a British Allotment
Hardware & Standards

Down the Plot, Up the Stack: A Season of LoRaWAN Sensors on a British Allotment

Eight soil-moisture nodes, one solar-powered gateway and a Grafana dashboard, run across the 2026 growing season on a UK allotment site. Here is what the radio link, the batteries, the enclosures and the data actually did when the weather stopped cooperating.

Two Kilowatts of Hope: What Smart Kettles Actually Do With a Litre of Water
Energy & Retrofit

Two Kilowatts of Hope: What Smart Kettles Actually Do With a Litre of Water

Four connected kettles, one dumb control and a calibrated power analyser: we measured real energy-to-boil, idle radio draw, keep-warm costs and whether a 70 °C setting actually reaches 70 °C. Some features earn their Wi-Fi. Most do not.

Energy & Retrofit

Counting the Kilowatt-Hours Twice: Auditing a SMETS2 Meter Against a Calibrated Logger

A SMETS2 electricity meter, its in-home display and a calibrated energy logger were logged side by side for 30 days. Daily totals agreed closely, but tariff boundaries and display rounding showed where a time-of-use household can misread its own data.

Contention at Teatime: A Month of Full-Fibre Throughput, Latency and Loss in a UK Home
Hardware & Standards

Contention at Teatime: A Month of Full-Fibre Throughput, Latency and Loss in a UK Home

A 900 Mbps full-fibre service was instrumented for 30 days to separate access-line performance from Wi-Fi and home-network effects. Wired throughput held close to the advertised median at peak, but latency and the tenth percentile told a more honest evening story.

Where the Watts Sleep: Seven Days of Standby Measurement in a British Home
Energy & Retrofit

Where the Watts Sleep: Seven Days of Standby Measurement in a British Home

A week with plug-in monitors and a whole-house logger in a Sheffield semi quantifies what stays awake when the house is quiet. The always-on floor is larger than most smart-home advice assumes, and much of it cannot sensibly be switched off at all.

Bench Versus Tarmac: Auditing E-Bike Battery Claims Against a Hilly British Route
Hardware & Standards

Bench Versus Tarmac: Auditing E-Bike Battery Claims Against a Hilly British Route

CavLab put four UK-market e-bike packs through a controlled discharge and charger test regime, then rode a fixed Pennine loop to see how bench watt-hours translate into real miles. The gap between nameplate capacity, usable energy and advertised range turns out to be engineering, not marketing alone.

Thirteen Amps of Caution: Taking Apart the British Plug to See What BS 1363 Still Gets Right
Hardware & Standards

Thirteen Amps of Caution: Taking Apart the British Plug to See What BS 1363 Still Gets Right

The UK three-pin plug is heavier, bulkier and more expensive than almost any rival — and it is still the safest domestic mains connector in common use. We dismantled one, traced the design decisions behind BS 1363, and asked whether a standard written for post-war copper shortages still fits a home full of EV chargers and heat pumps.

Cold Comfort: Instrumenting a Victorian Terrace to Test What Heat Pumps Actually Deliver
Energy & Retrofit

Cold Comfort: Instrumenting a Victorian Terrace to Test What Heat Pumps Actually Deliver

Solid walls, suspended timber floors and a bay window: the pre-1919 terrace is the hardest test in British retrofit. We built an instrumented rig to model one, ran it across a range of flow temperatures, and compared the measured results with the figures printed in manufacturer literature.