I can think of a couple of ways to say it:

1. Doble ang layo = Double the distance

2. Dalawang beses ang layo = Twice/Two times the distance

The first one would be the more common way to express it.

"Ang layo ng bahay mo.  Doble ang layo sa bahay ko."  = Your house is quite far.  It's twice the distance to my house.

"Layo" can be used to mean both distant and distance.