Yes, it sure looks like the first letter is an N- the bit Bumble provides definitely says "Nov".
So, I'd go for the place in question being "Nether House" /"Nitther house".
This is/was just at the bottom edge of Upperthong village and therefore well inside the larger area of Holmfirth which was known as Upperthong/Overthong both in PR's and the census.
PS- Holmfirth and the whole of West Yorkshire is under deep snow today- picturesque but cold.