断熱が悪いと、いくら暖房してもちっとも暖かくならない。

、。

If the insulation is poor, no matter how much you heat, it never gets warm.

Literal

Insulation [subject-が] bad-[if-と], however-much heating-did-[even-ても] at-all warm not-become.

断熱が悪い ('insulation is poor') uses 断熱 — the same compound that appears in 断熱材 (insulation material). いくら暖房しても ('no matter how much you heat') is the ~ても concessive with いくら for emphasis. ちっとも ('not at all') is the colloquial negative intensifier — stronger than 全然. ~ならない (negative of なる) is the outcome. A practical home-maintenance observation.