@Davidsont wifi signals are affected by the layout and type of construction of your home so every home is different. The Hub4 you have should deliver 500Mb?s in the same room it is in but inevitably speeds will drop as the signal has to pass through walls and solid objects. First point make sure that the hub is sighted in the best position which is on a surface in the open so it is above things like rasdiators and furniture.
Secondly if your home has solid internal walls you are going to struggle to get decent signal more than one room away so the answer is to have multiple wifi sources. Sky sell a system called Wifi Max which can come with up to 3 extenders which costs £7.50 a month. It also includes engineer visits if you need more than one extender to get 25Mb/s in every room.
You can buy your own gear if you prefer which should not be thst difficult to set up. As an example my 3 unit Deco M4 set up delivers 200Mb/s in the rooms 2 levels away from my Sky hub. Before rushing out to buy kit consider the speed you need as few apps need more than 100Mb/s in practice. Many download servers limit bandwidth. Activities like streaming video cannot use more than 30Mb/s for UHD.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
