Daylight is widely valued in residential decision-making, yet the economic literature still tends to treat its contribution to housing value as a linear attribute or to proxy it with legacy compliance metrics. This article develops a benchmark grounded nonlinear hedonic framework to investigate whether the market rewards daylight quantity alone or, more plausibly, a daylight comfort balance that combines useful illuminance, sunlight access, and manageable exposure. The study is anchored in the Turin condominium sample reported by Loro et al., which includes 100 apartments modeled through Climate Studio and characterized by contextual, architectural, energy, and daylight variables. The empirical motivation is specific and bounded: in the published ordinary least squares benchmark, estimated on 90 units and checked on a 10-unit control sample, useful daylight illuminance achieved (UDI.A) and annual sunlight exposure (ASE) were significant, whereas average daylight factor (DFm) and spatial daylight autonomy (sDA) were not, and the model explained about 59% of variation in listing price per square meter. Building on that published pattern, the manuscript strengthens the theoretical motivation, clarifies the interpretation of listing-price capitalization as a noncausal market signaling relation, and specifies a parsimonious semiparametric hedonic model with spline-based daylight terms and restricted interaction effects among UDI.A, ASE, blinds-closed time, and vertical sky component. The contribution is methodological and interpretive: a defensible comfort-frontier hypothesis, a transparent reanalysis protocol, and a benchmark-based validation path for future microdata implementation. By making explicit why comfort-proximate daylight metrics may matter more than legacy diffuse-sky indicators, the paper speaks directly to valuation practice, climate-based daylight assessment, and performance-based housing design.