Insulation boards and methods for their manufacture

A method for producing isocyanurate insulation foams, the method comprising:

• (i) forming a B-side stream of reactants including a polyol and a blowing agent blend, where the blowing agent blend includes isopentane and n-pentane at a weight ratio of isopentane to n-pentane of about 1:1 to about 2.7:1 in the substantial absence of cyclopentane, where said step of forming includes introducing the polyol and the blowing agent within a pin mixer under a pressure in excess of about 80 psi and a temperature in excess of about 10° C.;
• (ii) increasing the temperature of the B-side stream of reactants to a temperature of about 16° C. to about 29° C. and a pressure of about 1800 psi to about 2400 psi;
• (iii) after said step of increasing, delivering the B-side stream of reactants to a mix head, where the temperature of the B-side stream of reactants is increased to about 27° C. to about 35° C.;
• (iv) introducing an A-side stream of reactants to the mix head at a temperature of about 29° C. to about 35° C. and a pressure of about 1800 to about 2400 psi to thereby mix with the B-side stream and form a mixture of polyisocyanurate ingredients;
• (v) depositing the mixture of polyisocyanurate ingredients onto a laminator and allowing the mixture of polyisocyanurate ingredients to form a developing foam.