How do I estimate home improvement costs?

Get multiple contractor quotes, research material costs, and add 10-20% for unexpected expenses. Labor typically costs 50-65% of total project cost.

What home improvements add the most value?

Kitchen and bathroom remodels, new roofing, and energy-efficient upgrades typically provide the best return on investment.

DIY saves money on labor but risks quality issues. Hire contractors for electrical, plumbing, structural work, or permits required.

Raw Score (X)

Mean (μ)

Standard Deviation (σ)

Z = (X - μ) / σ

Z-Score

1.00

84.13%

Percentile

0.8413

P(X ≤ x)

0.1587

P(X > x)

Z-Score

Mean (μ)

Standard Deviation (σ)

129.40

Raw Score (X = μ + Z × σ)

Z-Score	Percentile	P(below)	Common Use
-3.00	0.13%	0.0013	Extreme low
-2.00	2.28%	0.0228	Very low
-1.00	15.87%	0.1587	Below average
0.00	50.00%	0.5000	Average (mean)
1.00	84.13%	0.8413	Above average
1.645	95.00%	0.9500	90% CI (one-tail)
1.96	97.50%	0.9750	95% CI (two-tail)
2.00	97.72%	0.9772	Very high
2.576	99.50%	0.9950	99% CI (two-tail)
3.00	99.87%	0.9987	Extreme high