diff --git a/src/layers/normalisation.jl b/src/layers/normalisation.jl
index a018a073..69854f44 100644
--- a/src/layers/normalisation.jl
+++ b/src/layers/normalisation.jl
@@ -113,15 +113,15 @@ function (BN::BatchNorm)(x)
   else
     T = eltype(x)
 
-    ϵ = T(BN.ϵ)
+    ϵ = data(convert(T, BN.ϵ))
     m = size(x, 2)  # batch size
     μ = mean(x, 2)
     σ = sqrt.(sum((x .- μ).^2, 2) ./ m .+ ϵ)
 
     # update moving mean/std
-    mtm = T(BN.momentum)
-    BN.μ = (1 - mtm) .* BN.μ .+ mtm .* μ.data
-    BN.σ = (1 - mtm) .* BN.σ .+ mtm .* σ.data .* m ./ (m - 1)
+    mtm = data(convert(T, BN.momentum))
+    BN.μ = (1 - mtm) .* BN.μ .+ mtm .* data(μ)
+    BN.σ = (1 - mtm) .* BN.σ .+ mtm .* data(σ) .* m ./ (m - 1)
   end
 
   λ.(γ .* ((x .- μ) ./ σ) .+ β)