The nation's homeowners filed fewer insurance claims this summer, but the average costs of them could soar to new heights. 

The 1,070,614 claims assignments between July and September represented the slowest summer in five years, according to risk analytics firm Verisk. The company is forecasting between 4.3 million and 4.5 million claims by year-end, another low mark aided by far fewer hurricane and tornado-related claims. 

Claims severity also averaged $16,755, a slight respite from the third quarters of the prior two years. Verisk however cautions that after a maturation period, in which high-value claims are processed, the figure could rise up between $17,258 to $18,431, which would be one of the highest-severity quarters in recent memory.

Rising reconstruction costs, including materials and labor, are a factor for the rise, the report said. The findings add to woes for homeowners who are spending well into double-digits on homeownership costs including insurance, maintenance and taxes, on top of still weighty home prices.

The numbers behind the homeowners insurance "paradox"

Verisk, which describes the diverging claims and cost figures as a paradox, said the number of claims over the summer was down 28.5% from the year prior. There was a 95% decrease in hurricane claims from last year's third quarter, and a 57% decline in tornado damage claims. 

Wind and hail accounted for 51% of all combined claims, including a massive spike in Wyoming following a hailstorm in August. The majority of claims, or 29.9%, were made for water losses, followed by 22.1% for hail and 16.2% for wind damages.

Residential reconstruction costs rose 3.52% from last October, with labor costs rising 4.49% over the same time, according to Verisk. Labor rose faster than materials, which rose 2.19% in the past 12 months, while lumber, which was subject to tariff swings this year, fell 1.52% in the U.S. 

The analytics company also noted the impact of the Palisades Fire in the Los Angeles region, where reconstruction costs have more than doubled to 7.36% compared to the national average.

Permits for new residential properties meanwhile are also down 8.16% from a year ago, and fell 0.85% in the prior three months, the report found. Homebuilder sentiment has remained low all year, and those companies and their mortgage arms have offered ultra-low rate promotions in recent months to nudge sluggish activity.