We have had in our house problems with condensation on our upstairs windows despite new windows and using dehumidifiers. After an internet search of the issue which we thought was humidity, we researched Envirovent and made a call to the company. Their representative Ollie visited, on time, very presentable and after some note-taking took a humidity reading of the house. The temperature inside is too warm with nowhere for the air to escape. His proposal was received next day, broken down, with 2 options and costings. We took option 1, getting a ventilation unit fitted into the upstairs landing ceiling and also one in the bathroom. We had two payment options, easy to use and paid 50% deposit. The fitter Mikey, arrived on time, again very presentable, sociable and completed the job to spec in 3 hours. No mess was left, the bathroom cleaned as was the landing and he did a show and tell of how to use the units (although they are always on and shouldn't need amending). The second half of payment was made via a secure payment link. We have seen no condensation (Winter is to come though) and the bathroom unit comes on immediately when the shower comes on to extract the hot air. The landing unit you can tell is working but is exceptionally quiet. I would have no hesitation recommending Envirovent.