Enclosure decisions are often made late and by a different team than the electrical design — which is exactly why they cause problems. An enclosure that looks right and protects the electronics can still trap heat until the board overheats, block a radio's signal until range drops well below spec, or fail an ingress-protection test that was assumed passing. Getting these three concerns — sealing, thermal, and RF — resolved together and early avoids expensive rework.
IP rating: sealing is a system, not just a gasket
Ingress Protection (IP) ratings specify protection against solid particles and liquids — the two digits after "IP" indicate dust and water resistance respectively, with higher numbers meaning stronger protection. Achieving a target IP rating isn't just about adding a gasket; it requires the entire enclosure system to cooperate: cable and connector glands rated for the same ingress level, screw bosses and seams that don't create leak paths, and buttons or membranes designed for the sealing requirement rather than a standard off-the-shelf part. A product designed for IP67 with a connector only rated IP54 is only as protected as its weakest point.
It's also worth deciding early whether the product needs to survive submersion (higher IP ratings) or just resist splashing and dust in a typical outdoor or industrial environment (moderate ratings) — over-specifying adds cost and complexity that isn't always needed, and under-specifying causes field failures that are expensive to fix after units have shipped.
Thermal: the enclosure decides where heat goes
A sealed enclosure that protects against IP ingress also blocks the natural airflow that would otherwise carry heat away from the board. For devices with any meaningful power dissipation — active radios, processors doing sustained work, charging circuitry — the enclosure material and geometry become part of the thermal design, not separate from it. Plastic enclosures are poor thermal conductors and tend to trap heat; metal enclosures (or metal inserts/heat spreaders within a plastic shell) can conduct heat to the case exterior, but introduce their own considerations for RF shielding and grounding.
The practical exercise is thermal modeling or at minimum a worst-case power dissipation estimate early in the design, checked against the enclosure's actual ability to shed that heat in the product's expected ambient temperature range — not assumed acceptable because a similar-looking product from another vendor seems fine.
RF: what the enclosure does to your antenna
| Enclosure material | RF impact |
|---|---|
| Plastic (ABS, polycarbonate) | Generally RF-transparent; minimal impact if antenna keep-out is respected |
| Metal (aluminum, steel) | Blocks/reflects RF significantly; requires an RF-transparent window or external antenna |
| Metallized plastic / paint / coatings | Can unexpectedly attenuate RF even though the base material wouldn't |
A metal enclosure chosen for thermal or durability reasons can silently degrade wireless range if the antenna doesn't have a clear RF path — either through an intentional plastic window in the housing, an external antenna, or careful placement relative to any metal structure. This is a common gap between hardware and industrial design teams: a metal enclosure decision made for mechanical reasons without RF input can undo weeks of careful antenna and RF layout work on the PCB.
Getting all three resolved together
Because sealing, thermal, and RF concerns interact — a sealed enclosure traps heat, a metal enclosure that helps with heat blocks RF, RF windows can create sealing challenges — the practical approach is to involve mechanical, electrical, and RF considerations in the same design review rather than sequentially. A design that satisfies each concern in isolation but wasn't checked against the others is where these conflicts usually surface, often in the first prototype build rather than earlier when they'd be cheap to fix.
How we approach this
Enclosure requirements get factored into the electrical and RF design from early on, rather than handed off as a separate industrial-design track. See our embedded hardware work for how this fits into a full hardware build, from schematic through DFM.