  This article is devoted to define and solve an evolution equation of the form
$dy_t=\Delta y_t dt+ dX_t(y_t)$, where $\Delta$ stands for the Laplace operator
on a space of the form $L^p(\mathbb{R}^n)$, and $X$ is a finite dimensional
noisy nonlinearity whose typical form is given by $X_t(\varphi)=\sum_{i=1}^N
x^{i}_t f_i(\varphi)$, where each $x=(x^{(1)},...,x^{(N)})$ is a
$\gamma$-H\"older function generating a rough path and each $f_i$ is a smooth
enough function defined on $L^p(\mathbb{R}^n)$. The generalization of the usual
rough path theory allowing to cope with such kind of systems is carefully
constructed.
