A timber frame house has a structural frame of engineered timber studs, rails and sheathing that carries the loads of the building, with insulation between and often outside the studs. The external finish may be brick, block, render or cladding, so a timber frame house can look identical to a masonry one.
The timber frame is usually manufactured off site as panels and erected quickly, giving a weathertight shell sooner than traditional masonry. The insulation sits within the frame depth, often with additional insulated sheathing, and a vapour control layer on the warm side manages moisture movement.
Correct construction depends on keeping the frame dry, maintaining the breather membrane and ventilated cavity behind any external leaf, and ensuring the vapour control layer is continuous. These are ordinary requirements of the system rather than drawbacks, but they need attention on site.