This site has some answers that might help you: https://www.hunker.com/13402164/dimensions-of-standard-hearths
Here are some ideas as well to look at in addition to Holly's! Good luck.
https://inspectapedia.com/chimneys/Fireplace_Hearth_Specifications.php
https://www.bespokemarblefireplaces.co.uk/guides/the-average-height-for-a-fireplace-hearth-base-section-of-fire-surround-from-the-floor-is-50mm-total-thickness.html
https://www.hunker.com/13402164/dimensions-of-standard-hearths
It depends on the fireplace size. The link above is good. I have a gas fireplace, so I don't have a hearth. For a wood burning fireplace, the width has to be wider than the firebox and deep enough to catch sparks.
Consult the Building Regulations for restrictions on proximity of combustible materials
It is about 4ft tall by 45 in wide. I'd like to use a 2x4 built box. I need ideas for ways to cover using tile or faux stone (not too heavy).
my fireplace is real field stone and when it was constructed there were a few spots that needed more stone and Ihave no idea how to fix it simply
Economical to run, will heat a 500 sq ft room, good warranty and will hold up.
This site has some answers that might help you: https://www.hunker.com/13402164/dimensions-of-standard-hearths
Here are some ideas as well to look at in addition to Holly's! Good luck.
https://inspectapedia.com/chimneys/Fireplace_Hearth_Specifications.php
https://www.bespokemarblefireplaces.co.uk/guides/the-average-height-for-a-fireplace-hearth-base-section-of-fire-surround-from-the-floor-is-50mm-total-thickness.html
https://www.hunker.com/13402164/dimensions-of-standard-hearths
It depends on the fireplace size. The link above is good. I have a gas fireplace, so I don't have a hearth. For a wood burning fireplace, the width has to be wider than the firebox and deep enough to catch sparks.
Consult the Building Regulations for restrictions on proximity of combustible materials