A search for a massive resonance {mathrm{W}^{prime }}decaying into a W and a Higgs boson in the ell nu mathrm{b} overline{mathrm{b}} (ell = mathrm {e}, mu ) final state is presented. Results are based on data corresponding to an integrated luminosity of 19.7,text {fb}^{{-1}} of proton–proton collisions at sqrt{s}=8 ~text {TeV}, collected using the CMS detector at the LHC. For a high-mass (gtrsim 1~text {TeV}) resonance, the two bottom quarks coming from the Higgs boson decay are reconstructed as a single jet, which can be tagged by placing requirements on its substructure and flavour. Exclusion limits at 95 % confidence level are set on the production cross section of a narrow resonance decaying into WH, as a function of its mass. In the context of a little Higgs model, a lower limit on the {mathrm{W}^{prime }} mass of 1.4~text {TeV} is set. In a heavy vector triplet model that mimics the properties of composite Higgs models, a lower limit on the {mathrm{W}^{prime }} mass of 1.5~text {TeV} is set. In the context of this model, the results are combined with related searches to obtain a lower limit on the {mathrm{W}^{prime }} mass of 1.8~text {TeV}, the most restrictive to date for decays to a pair of standard model bosons.