The pattern book has been produced by Tai ar y Cyd, a collaboration of 23 Welsh social landlords and is supported by Welsh Government.
Lluniwyd y llyfr patrymau gan Tai ar y Cyd, cydweithrediad rhwng 23 o landlordiaid cymdeithasol Cymru ac mae'n cael ei gefnogi gan Lywodraeth Cymru.