Can I still claim the Insulation expense from 3 years go?

[Carolineling2020]

I replaced the whole house siding and insulation in 2018/2019. But I didn't claim that expense for my 2018 or 2019 tax return. Can I claim that in 2021 tax return? 

Thanks!

[Mike9241]

No. if you are entitled to any credit you'll have to amended 2018/19