Is three routers better than two for WiFi?

Question

I have a five room, 114m^2 (1200square feet), single story apartment. I have two routers set up. One working as a proper router and one functioning as a pure WAP (it has wired access itself). It is very clear from careful measurement that I definitely need two routers as opposed to one to get good WiFi coverage in the whole apartment.

I have set up these routers in opposite ends of the apartment (It would perhaps have been better to have a single router in the center of the apartment, but that is not possible for several practical reasons).

Now, I already own a third router (hardware identical to the WAP) that I could set up as a second WAP, potentially forming a fairly equilateral triangle of routers. The third router would also have wired access itself.

Will I get even better WiFi reception with a third router? Or will the routers interfere with each other, and perhaps even make the reception worse? (It is a big apartment house, so there are already plenty of WiFi routers in the vicinity)

The hardware in question is an ASUS RT-N56U Dual-band Wireless-N Gigabit Router Router as main router and two Netgear WNDR3700v1 (running DD-WRT) as WAP. So all routers have dual-band, support 11n, and are fairly high-end. They are all configured to auto-select appropriate channels.

Answer 1

Two is plenty for 1200 sq. ft. If there is a lot of interference in your apartment, then you may add another. However, if the routers are on different channels, then they should not interfere with one another.

Answer 2

This is not a direct answer to your question, but if I were you, I would:

1. draw a rough top-view-map of the house
2. get Wifi signal analyzer software (for android, iphone or laptop)
3. create a heat map for the wifi signal.

You might also try Meraki WiFi Mapper service.

I have apartment of more than 140 meters and it is covered with just one ADSL router placed at the middle, but signal is weak at the both ends.